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2604.20333 2026-05-11 cs.NE

Quantization robustness from dense representations of sparse functions in high-capacity kernel associative memory

Akira Tamamori

AI总结 本文研究了基于核逻辑回归(KLR)的高容量联想记忆网络在压缩方面的可行性,旨在揭示其鲁棒表示的几何原理。通过自发对称性破缺和沃尔什分析,提出了一个几何解释框架,并通过量化与剪枝实验验证,发现网络在低精度量化下保持鲁棒,但对剪枝高度敏感。这一现象可由“稀疏函数、密集表示”原理解释,为构建高效硬件实现的核联想记忆系统提供了理论依据。

Comments 11 pages, 9 figures

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英文摘要

High-capacity associative memories based on Kernel Logistic Regression (KLR) achieve strong retrieval performance but typically require substantial computational resources. This paper investigates the compressibility of KLR Hopfield networks to clarify the geometric principles underlying their robust representations. We present a geometric interpretation based on spontaneous symmetry breaking and Walsh analysis, and examine it through compression experiments involving quantization and pruning. The experiments reveal a clear asymmetry: the network remains robust under low-precision quantization while exhibiting strong sensitivity to pruning. We interpret this behavior through a "sparse function, dense representation" principle, in which a sparse input mapping is implemented through a dense bimodal parameterization. These findings suggest a practical route toward hardware-efficient kernel associative memories and provide insight into the geometric principles underlying robust representation in neural systems.

2604.19808 2026-05-11 cs.IT cs.ET math.IT

Anchor-Aided Multi-User Semantic Communication with Adaptive Decoders

Loc X. Nguyen, Phuong-Nam Tran, Trung Thanh Pham, Avi Deb Raha, Eui-Nam Huh, Zhu Han, Choong Seon Hong

AI总结 本文研究了多用户语义通信系统中的编码器-解码器设计问题,提出了一种基于自适应解码器的锚定语义通信框架。为了解决多用户场景下模型遗忘和计算能力差异带来的挑战,作者设计了一个与编码器结构对称的锚定解码器,用于在训练过程中保持编码器的语义表达能力,并为不同用户定制对应的解码器。该方法有效提升了通信系统的优化效率和语义信息的准确还原能力,实验结果验证了其优于现有方法的性能。

Comments 15 pages, 7 figures

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英文摘要

Semantic communication (SemCom) is accelerating its momentum to catch up with the massive increase in users' demands in both quantity and quality, with the assistance of advanced deep learning (DL) techniques. Specifically, SemCom can actively embed the semantic meaning of the data into the transmission process, while eliminating statistical redundancy to preserve bandwidth resources for other users. Therefore, the transmitter encodes the message in the most concise way, while the receiver tries to interpret the message with the DL model and its knowledge of the transmitter's intended meaning. Most existing works only consider one transmitter and one receiver, which limits their ability to address the diversity in users' models and capabilities. Therefore, in this paper, we propose a multi-user semantic communication system where each user is equipped with a distinct DL-based joint source-channel decoder architecture, reflecting the diversity in computing capacity. The challenging issue with the proposed system is the catastrophic forgetting property of neural networks, where the DL-based encoder fails to encode the data for the previous user when being trained with a new user. To address this, we propose an anchor decoder with an architecture that is symmetric to the encoder. The symmetric decoder has the same computational capacity as the encoder, providing feedback that aligns with the encoder's extraction capabilities and enhances optimization efficiency. The parameters of the optimized encoder are then frozen and used to train decoders for various users, aligning them with the encoder outputs. Finally, we conduct a series of simulation experiments to validate the proposed framework against other benchmarks.

2604.16713 2026-05-11 cond-mat.mes-hall quant-ph

Anisotropic spin-valley coupling in SiMOS and Si/SiGe quantum dots

N. Tobias Jacobson, Natalie D. Foster, Ryan M. Jock, Martin Rudolph, Andrew M. Mounce, Daniel R. Ward, Malcolm S. Carroll, Dwight R. Luhman

AI总结 本研究探讨了硅基量子点中各向异性的自旋- valleys 耦合现象,重点分析了SiMOS和Si/SiGe两种常见材料平台中的自旋轨道耦合特性。通过测量外加磁场方向和强度对自旋- valleys 耦合的影响,构建了物理模型以准确描述 valley 内部和 valley 之间的耦合机制,并比较了两种材料系统的差异。研究发现,尽管两者 $g$-因子差异相近,但SiMOS量子点的自旋- valleys 耦合强度比Si/SiGe高一个数量级,且两者在磁场方向上的耦合依赖性相似,为优化量子比特操作提供了重要参考。

Comments 16 pages, 13 figures

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英文摘要

While bulk silicon has long been understood to exhibit relatively weak spin-orbit coupling (SOC), confinement of electrons to quantum dots (QDs) at a silicon heterointerface results in significantly larger SOC. This is a concern for electron spin qubit performance, as intravalley and intervalley SOC can significantly perturb the operation of electron spin qubits. While these interactions can be harnessed to drive coherent rotations in a singlet-triplet qubit, coupling to low-lying excited valley states can lead to undesirable spin relaxation when valley splitting is on resonance with the Zeeman energy. In this work, we measure the angular dependence of the interfacial spin-orbit interaction as a function of the direction and magnitude of an applied external magnetic field in SiMOS and Si/SiGe heterostructures, two common material platforms for silicon spin qubits. We construct a physical model that accurately infers intra- and inter-valley SOC physics from fits to the data, allowing for a direct comparison between these two material systems. For the devices measured we find that, while the $g$-factor differences are comparable, the SiMOS QDs exhibit an order of magnitude larger spin-valley coupling than for Si/SiGe. Moreover, we find that the angular dependence of the spin-valley coupling is similar for both devices, with similar magnetic field orientations minimizing the spin-valley coupling. Our work points towards operational schemes for optimizing spin-valley coupling to avoid or exploit this mechanism for qubit operation.

2604.15122 2026-05-11 hep-ph hep-th

Symmetry Preserving Contact Interaction Approaches: An Overview of Meson and Diquark Form Factors

L. X. Gutiérrez-Guerrero, Roger José Hernández-Pinto

AI总结 本文综述了用于描述介子和二夸克结构的对称性保持接触相互作用模型,重点介绍了其在质量谱和弹性形变因子方面的应用。该模型提供了一种简单而一致的非微扰QCD处理方法,能够处理基态和激发态,并通过对比最新理论结果和实验数据,进一步验证了其有效性与局限性。文章还比较了该模型与其他理论方法如格点QCD的异同,并展望了未来实验计划如FAIR、杰斐逊实验室和电子离子对撞机在强子结构研究中的重要作用。

Comments 45 pages, 18 figures, review article. Accepted for publication in Particles (MDPI), 2026

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Journal ref
2026
英文摘要

We present an updated overview of the symmetry preserving Contact Interaction model in hadronic physics, developed a little over a decade ago to describe the mass spectrum and internal structure of mesons and diquarks composed of light and heavy quarks. Over the years, the Contact Interaction has evolved into a framework capable of treating both ground and excited states, providing a simple yet consistent approach to nonperturbative QCD. In this review, we examine the mass spectrum and elastic form factors of forty mesons with different spins and parities, together with their corresponding diquark partners. Importantly, we update the comparison of Contact Interaction predictions using recent results from the literature, offering a fresh perspective on the model's performance, strengths, and limitations. The analysis presented here refines previous conclusions and supports the Contact Interaction as a practical tool for hadron structure studies, with potential applications to baryons and multiquark states. We also present comparisons with other theoretical models and approaches, including lattice quantum chromodynamics, and comment on future prospects in view of ongoing and planned hadron structure experimental programs. In particular, forthcoming measurements at FAIR, together with future studies at Jefferson Lab and the Electron Ion Collider, are expected to provide key insights into hadron structure, with FAIR offering indirect constraints via hadron spectroscopy, hadronic interactions, and in-medium properties, while high-precision data on meson structure and form factors from Jefferson Lab and the Electron Ion Collider will provide valuable benchmarks to confront Contact Interaction based predictions.

2604.14436 2026-05-11 hep-th

Half-BPS Impurity Backgrounds and Supersymmetry

D. Bazeia, A. C. Lehum

AI总结 本文研究了二维空间中具有杂质形变的半BPS背景及其超对称性,提出了一种基于实背景超场(spurion)的刚性$\mathscr{N}=(1,1)$超空间框架,从而在作用量层面实现对杂质形变的显式超对称描述。通过分析静态界面型配置,确定了半BPS条件及其对应的超对称投影算符,并推导出相应的BPS方程和能量的精确Bogomol'nyi完成,揭示了BPS解所满足的紧致能量下界。研究还指出坐标依赖和导数依赖的杂质耦合可能破坏Bogomol'nyi结构,从而强调了保持超对称控制的spurion扩展的重要性。

Comments 8 pages. Accepted for publication in Eur. Phys. J. C

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Journal ref
Eur. Phys. J. C 86, 479 (2026)
英文摘要

We develop a rigid $\mathscr{N} =(1,1)$ superspace framework for spatially inhomogeneous impurity deformations in $D=1+1$ dimensions by embedding the impurity profile into a real background superfield (spurion). This spurionic completion provides a manifestly supersymmetric description at the level of the action and offers a systematic route to identify which inhomogeneous backgrounds preserve a nontrivial subset of supercharges. Focusing on static interface-type configurations, we determine the half-BPS condition on the spurion background and the corresponding supersymmetry projector. In the resulting half-BPS sector we derive the associated first-order BPS equation for static bosonic matter configurations and establish an exact Bogomol'nyi completion of the static energy, yielding a sharp bound saturated by BPS solutions. We further comment on how explicit coordinate dependence and derivative-dependent impurity couplings can obstruct the Bogomol'nyi structure, thereby motivating spurionic extensions that retain supersymmetric control over inhomogeneous deformations.

2604.11217 2026-05-11 physics.optics

Recovery of tunable bound states in the continuum

Hai Huang, Huiming Zhang, Biye Xie, Wengang Bi, Daquan Zhang

AI总结 该研究探讨了如何在光子晶体平板中恢复可调谐的连续统中束缚态(BIC),这些态在实际集成平台中常因衬底引起的镜像对称性破坏而退化为有限品质因子的准BIC。通过引入一个独立的奇宇称扰动,研究提出了一种双不对称策略,能够精确抵消衬底引发的辐射通道,从而恢复BIC的奇异性及其可调谐特性。该方法不仅恢复了BIC的极化涡旋和品质因子与波矢差的平方反比关系,还揭示了模式依赖的补偿规律,并适用于更高阶的拓扑共振态。

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英文摘要

Tunable bound states in the continuum (BICs) in photonic crystal slabs are highly sensitive to substrate-induced mirror-symmetry breaking and typically degrade into finite-$Q$ quasi-BICs in realistic integrated platforms. Here we show that such degradation can be deterministically reversed. Using temporal coupled-mode theory and full-wave simulations, we demonstrate that the radiation channel opened by the substrate can be exactly cancelled by introducing a second, independent odd-parity perturbation inside the slab. This dual-asymmetry strategy restores the singularity of the radiation matrix and thereby recovers a tunable BIC in a substrate-supported photonic crystal slab. The recovered state regains both the polarization vortex and the characteristic $Q\propto Δk^{-2}$ scaling. The recovery points further follow a linear relation in the two-asymmetry parameter space, revealing a simple mode-dependent compensation law. The same mechanism also restores merging-BIC configurations, showing that it applies not only to isolated tunable BICs but also to higher-order topological resonance states built from them. Our results establish a practical route for preserving tunable topological resonances in substrate-supported nanophotonic systems.

2604.10230 2026-05-11 cond-mat.str-el

A Scalable Configuration-Interaction Impurity Solver via Active Learning

Jeongmoo Lee, Ara Go

AI总结 该研究提出了一种基于主动学习的自适应截断组态相互作用方法(AL-ATCI),用于解决有限哈密顿量杂质问题。该方法通过主动学习策略识别与关联态相关的组态空间,有效控制计算复杂度,并在无需外部基准的情况下提供内部收敛参数。实验表明,该方法在保持高精度的同时显著降低了计算成本,适用于更大尺寸的杂质系统和更多轨道的计算,为精确求解强关联多体问题提供了更高效的工具。

Comments 5 pages, 4 figures, supplemental material included

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英文摘要

Finite-Hamiltonian impurity solvers provide direct real-frequency spectra and a natural route to enlarged impurity Hamiltonians, but their applicability is limited by the rapid Hilbert-space growth with the number of bath or other added one-particle orbitals. We introduce an active-learning extension of adaptive-truncation configuration interaction (AL-ATCI) that identifies the determinant manifold relevant to the correlated state. The approximation is systematically controlled by the query size N_query, which also provides an internal convergence parameter when no external benchmark is available. Over the benchmark range studied here, the computational cost grows only weakly with bath size, because enlarging the bath mainly expands the combinatorial determinant space rather than the physically relevant manifold. In dynamical mean-field-theory benchmarks for the one-dimensional Hubbard model, AL-ATCI reproduces exact-diagonalization accuracy and extends cellular calculations to clusters as large as N_c = 10. For a three-orbital rotationally invariant Sr2RuO4 impurity problem, we demonstrate systematic convergence of dynamical quantities and a highly compressed configuration space as N_b is increased from 9 to 18. These results substantially alleviate the bath-discretization bottleneck of exact-diagonalization- and configuration-interaction-based impurity solvers and make large-bath and enlarged-orbital calculations more practical.

2604.10020 2026-05-11 math.PR math-ph math.MP

The directed landscape in half-space

Duncan Dauvergne, Lingfu Zhang

AI总结 本文研究了两类属于KPZ普适类的半空间模型——指数型最短路径渗透模型和广义彩色TASEP模型,证明它们在适当缩放下收敛于同一个极限对象——半空间定向景观。该景观是一个随机定向度量,其行为由边界相互作用强度参数决定。研究还通过半空间KPZ固定点刻画了该景观,并给出了几何路径的收敛性以及多种模型的联合平稳测度的显式构造,为理解半空间中随机生长过程的共性提供了重要理论依据。

Comments 94 pages, 2 figures

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英文摘要

We prove that two half-space models in the KPZ universality class, exponential last-passage percolation and a family of Poisson-avoiding metrics generalizing colored TASEP, converge to a common scaling limit. This scaling limit is the directed landscape in half-space, a random directed metric in the half-plane indexed by a parameter which determines the strength of the boundary interaction. As part of our analysis, we characterize the half-space directed landscape in terms of the half-space KPZ fixed point, and prove convergence of geodesics. We also give an explicit construction of joint stationary measures (or horizons) in half-space for the log-gamma polymer, the KPZ equation, exponential and geometric last passage percolation, and the directed landscape itself.

2604.09238 2026-05-11 physics.ins-det

Optical readout of MPGDs with solid wavelength shifters

F. M. Brunbauer, A. Cools, M. Cortesi, E. Fasoula, E. Ferrer-Ribas, K. J. Flöthner, F. Garcia, D. Janssens, M. Lisowska, P. Sviatopolk Mirsky, H. Müller, J. Nummi, E. Oliveri, G. Orlandini, T. Papaevangelou, D. Pfeiffer, E. Pollacco, L. Ropelewski, F. Sauli, J. Samarati, L. Scharenberg, M. van Stenis, R. Veenhof

AI总结 该研究探讨了利用固体波长转换材料对微图案气体探测器(MPGD)进行光学读出的可行性,旨在减少对温室气体CF₄的依赖。通过在玻璃微梅格(Micromegas)阳极上涂覆四苯基丁二烯(TPB)等固体波长转换层,实现了0.22毫米的高空间分辨率。研究还表明,TPB层与光学读出的气体电子倍增器(GEM)结合也能达到中等水平的空间分辨率,为探测器设计提供了新的替代方案。

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英文摘要

Optical readout of MicroPattern Gaseous Detectors (MPGDs) makes use of the high granularity of imaging sensors to achieve good spatial resolution for radiation imaging and particle detection. CF4 is widely used as a scintillating gas because its emission lies in the visible range, where optical sensors are most sensitive. However, to reduce reliance on greenhouse gas, such as CF4, which also has limited availability, alternative gas mixtures emitting scintillation light in the ultraviolet range can be used in combination with wavelength shifters. We investigate the spatial resolution achievable with optically read out Gaseous Electron Multipliers (GEMs) and Micromegas when using solid wavelength shifter layers such as Tetraphenyl butadiene (TPB). TPB coatings on the anode of glass Micromegas achieve the best spatial resolution of 0.22 mm owing to the minimal distance between the origin of the scintillation light and the wavelength shifter. Nevertheless, TPB layers were also shown to achieve moderate spatial resolution in combination with optically read out GEMs.

2604.08183 2026-05-11 gr-qc hep-th

Positivity of holographic energy

Piotr T. Chruściel, Raphaela Wutte

AI总结 本文研究了具有负宇宙学常数的四维时空的全息能量的正性问题,针对其共形无限边界为共形静态且具有球形或环形截面(并满足自旋结构兼容条件)的情形。作者通过严格的数学证明,确立了加权全息能量的正性,为相关引力理论提供了重要的分析工具和理论支持。

Comments 7 pages

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Journal ref
Phys. Rev. Lett. 136, 181401 (2026)
英文摘要

We prove positivity of a weighted holographic energy for four-dimensional spacetimes with negative cosmological constant whose conformal boundary at infinity is conformally static and admits either spherical sections, or toroidal sections with compatible spin structure.

2604.07920 2026-05-11 astro-ph.IM

First Lunar Farside SETI Observations for Periodic Signals with the Low-frequency Radio Spectrometer of Chang'E-4 Mission

Jian-Kang Li, Zhen-Zhao Tao, Bo-Lun Huang, Kang-Jiao, Tong-Jie Zhang, Ming-Yuan Wang, Jin-Song Ping, Dan Werthimer, Vishal Gajjar

AI总结 本文利用嫦娥四号任务中的低频射电谱仪,在月球背面首次开展了搜寻周期性人工信号的射电天文观测。研究采用主成分分析、天线间基底对齐以及时间周期性和频率梳结构诊断等方法,对观测数据进行了深入分析,但未发现可信的周期性人工信号。该研究为月球背面射电搜寻地外文明(SETI)提供了方法框架,为未来相关研究奠定了基础。

Comments 12 pages, 6 figures, 2 tables. Submitted to AAS Journals

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英文摘要

Chang'E-4 (CE4), the first mission to soft-land on the lunar farside, provides a unique opportunity for astronomical observations from an environment shielded from terrestrial radio interference, and thus serves as pathfinder for lunar farside radio search for extraterrestrial intelligence (SETI) studies. We present a search for periodic technosignatures using low-frequency radio observations from the CE-4 mission, the first radio SETI study based on data from on the observation in lunar farside. We analyze the CE4 dynamic spectra with a component-level framework that combines principal component analysis (PCA), cross-antenna basis alignment, as well as temporal periodicity and frequency comb structure diagnostics. No final periodic candidate signal is found after the selection procedure, and we therefore find no evidence in the present CE4 sample for a credible periodic artificial signal. This study serves as a pathfinder and provides a practical framework for lunar radio SETI analysis. As more future lunar missions begin to incorporate radio instrumentation, lunar farside may become a promising site for expanding radio SETI research.

2604.07256 2026-05-11 hep-lat astro-ph.CO hep-ph hep-th

Revisiting the sphaleron and axion production rates in QCD at high temperatures

Sayak Guin, Sayantan Sharma

AI总结 本文通过格点方法重新计算了高温QCD中磁标度以下软胶子体系内的 sphaleron 率,覆盖了从 0.6 到 $10^{15}$ GeV 的广泛温度范围。研究比较了热场论与非热等离子体中的 sphaleron 率,估算了宇宙暴胀后重新加热早期阶段软胶子的热化时间。同时,论文还计算了由这些非微扰软胶子产生的相对论轴子的热产生率,发现其在电弱能标下与微扰估计存在显著偏差。

Comments v2; Discussions mainly in Section IV B updated and references added

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英文摘要

We report our new lattice results for the sphaleron rate calculated within a thermal effective field theory of soft SU(N) gluons whose momenta are below the magnetic scale, where $N=2,3$, for a wide range of temperatures spanning from $0.6$-$10^{15}$ GeV at sufficiently large volumes. Comparing these results with sphaleron rates in a non-thermal SU(N) plasma where the infrared gluons are over-occupied, we estimate the typical thermalization time for these ultra-soft soft gluons during the early stages of reheating after inflation. We also calculate the thermal production rate of relativistic axions due to these non-perturbatively interacting soft gluons which shows a significant deviation from its perturbative estimate even at the electroweak scale.

2604.06545 2026-05-11 math.AP physics.flu-dyn

Global well-posedness of the one-phase Muskat problem with surface tension

Hongjie Dong, Hyunwoo Kwon

AI总结 本文研究了带有表面张力的一相Muskat问题在全球范围内的适定性,针对小初始数据的情形,证明了该问题存在唯一的全局强解。该问题描述了多孔介质中湿润区与干燥区界面的运动,受达西定律支配。研究还表明,随着时间趋于无穷,解在Lipschitz范数下趋于零,这是该问题首次关于全局适定性的严格结果。

Comments 40 pages; v3. added references and fixed some typo

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英文摘要

In this paper, we establish the global well-posedness of the one-phase Muskat problem with surface tension for small initial data. This problem describes the motion of the interface separating a wet region from a dry region within a porous medium, a process governed by Darcy's law. Although physically essential, the inclusion of surface tension introduces an additional challenge. We prove that if the initial free boundary is sufficiently small in $H^s$, $s>d/2+1$, then the problem admits a unique global strong solution. Moreover, the solution converges to zero in Lipschitz norm as $t\rightarrow\infty$. To the best of our knowledge, this work constitutes the first global well-posedness result for the one-phase Muskat problem with surface tension.

2604.05728 2026-05-11 math.GR

An improved characterisation of inner automorphisms of groups

Francesco Fournier-Facio

AI总结 本文研究了群的内自同构的刻画问题,证明了每个群 $G$ 都可以嵌入到一个单群、完全且共Hopfian的群 $H$ 中,并且该嵌入是良性的。这一结果表明,$G$ 的非平凡自同态可以扩展到 $H$ 当且仅当它是 $G$ 的内自同构,从而加强了Schupp的定理并回答了Bergman的问题。

Comments 7 pages. v2: small changes

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英文摘要

We show that every group $G$ embeds malnormally into a simple, complete co-Hopfian group $H$. This implies that a non-trivial endomorphism of $G$ extends to $H$ if and only if it is an inner automorphism, strengthening a theorem of Schupp and answering a question of Bergman.

2604.05241 2026-05-11 math.ST stat.TH

Information Geometry and Asymptotic Theory for SMML Estimators

Enes Makalic, Daniel F. Schmidt

AI总结 本文研究了严格最小消息长度(SMML)估计器的信息几何性质及其渐近理论。作者将SMML目标分解为断言熵和条件交叉熵,揭示了其在模型选择与数据编码之间的平衡机制,并证明在高分辨率条件下,最优SMML划分可由最大似然估计器拉回参数空间中的加权费舍尔-拉奥沃罗诺伊划分得到。研究还表明,对于正则指数族,SMML码点满足矩匹配条件,可解释为KL/Bregman中心,为信息几何下的编码理论提供了新的几何解释。

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英文摘要

Strict minimum message length (SMML) is an information-theoretic coding principle that represents a continuous statistical model by a finite set of assertions and a partition of the sample space. We show that the SMML objective decomposes into assertion entropy and conditional cross-entropy, balancing the cost of identifying an assertion against the cost of encoding data under the assigned model. For any fixed partition, the optimal codepoint for each cell is the model distribution that minimises Kullback-Leibler divergence from the data distribution restricted to that cell. Using the local Fisher-Rao geometry of regular parametric models, we show that, under high-resolution regularity conditions, optimal SMML partitions are asymptotically the pullback, through the maximum likelihood estimator, of weighted Fisher-Rao Voronoi tessellations in parameter space, with assertion probabilities appearing as additive weights. For regular exponential families, SMML codepoints satisfy a moment-matching condition and admit an interpretation as KL/Bregman centroids, while exact SMML cells are pullbacks of convex polyhedra in sufficient-statistic space. Together, these results show that SMML induces a natural information-geometric quantisation linking entropy-based coding, KL projection, and divergence-based Voronoi geometry.

2604.03921 2026-05-11 eess.SY cs.SY

Cooperative $\mathcal{H}_\infty$ Fault-Tolerant Tracking with ISS Guarantees for Networked Systems with Sensor Faults

Moh Kamalul Wafi, Yurid E. Nugraha, Bambang L. Widjiantoro, Katherin Indriawati

AI总结 本文提出了一种针对存在传感器故障和外部干扰的异构网络化线性系统的协同容错跟踪控制框架。该方法采用增强的$\mathcal{H}_\infty$观测器同时估计系统状态和未知传感器故障,并通过凸优化的$\mathcal{H}_\infty$线性矩阵不等式合成内环状态反馈增益,以确保闭环系统的鲁棒稳定性和抗干扰能力;外环分布式积分作用则用于消除稳态跟踪误差并实现协同跟踪。研究证明,所提方法在干扰和估计误差影响下满足输入到状态稳定性(ISS),并在无干扰情况下实现指数收敛,数值实验验证了其在不同通信拓扑下的有效性与鲁棒性。

Comments This paper is accepted for publication at the 15th Asian Control Conference (ASCC) 2026

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This paper develops a cooperative fault-tolerant tracking framework for heterogeneous networked linear systems subject to sensor faults and external disturbances. Each unit employs an augmented $\mathcal{H}_\infty$ observer that jointly reconstructs the system state and unknown sensor fault, providing disturbance-attenuated estimation guarantees. An inner state-feedback gain is synthesized through convex $\mathcal{H}_\infty$ Linear Matrix Inequalities (LMIs) to ensure robust closed-loop stabilization and disturbance rejection, while an outer distributed integral action eliminates steady-state tracking offsets and enables cooperative tracking of a setpoint source. The resulting cooperative error dynamics are shown to satisfy an Input-to-State Stability (ISS) property with respect to disturbances and residual estimation uncertainty, and converge exponentially to zero in the disturbance-free case. Furthermore, vanishing cooperative error guarantees network-wide consensus tracking of the desired setpoint. Numerical studies on heterogeneous DC-motor networks with star, cyclic, and path communication topologies demonstrate accurate state and fault estimation, robust cooperative tracking, and resilience against disturbances and time-varying sensor faults. The proposed framework provides a scalable and robust coordination strategy for interconnected systems operating under sensing imperfections and uncertain environments.

2604.02470 2026-05-11 astro-ph.CO

Return to the Great Attractor: Strong Evidence for a Steradian-sized Flow Converging at $\sim$70 Mpc within the GA Supercluster and Aligned with the CMB Dipole

Alan Dressler, Andrew Monson

AI总结 该研究利用高精度的表面亮度涨落(SBF)测距技术,分析了66个红移在2000至5000 km/s之间的星系,以探测宇宙微波背景(CMB)偶极各向异性的起源。研究发现,银河系附近存在一个跨越球面角约1 steradian的大尺度引力流,其速度在约1000 km/s左右,并在约70 Mpc处汇聚,这一结果支持“Great Attractor”超星系团是CMB偶极的主要引力源。研究还指出,只有像SBF这样高精度的测距方法才能厘清CMB偶极是否由本地大尺度结构引起。

Comments 30 pages, 1 Table, 19 Figures

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We used the FourStar near-IR camera on Magellan-Baade to obtain high S/N H-Band imaging of 66 galaxies with radial velocities of 2000 < V < 5000 km/s. Our goal was to use the superior distance measurements of surface-brightness-fluctuations (SBF) to derive ``peculiar velocities'' to test claims that the CMB dipole anisotropy, equivalent to $\approx$600 km/s with respect to the Local Group, arises from a 'local' overdensity in the galaxy/dark-matter distribution -- the Great Attractor. SBF's ability to measure distances with 5% accuracy confirms a strong flow over a steradian of the sky peaking at Vpec $\sim$ 1000 km/s and converging to zero at D $\approx$70 Mpc from the Local Group. The modest spatial extent of this flow $R_V$ $\sim$ 5000 km/s is consistent with the original Great Attractor model (a diameter D $\sim$ 140 Mpc), as well as the magnitude and direction of the CMB dipole anisotropy, and the power spectrum of CMB fluctuations -- the latter two arguably the most secure measurements in astrophysics. In contrast, our results are at-odds with reports of comparable amplitude 'bulk flows' on scales of hundreds of Mpc that themselves may be inconsistent with the expected fluctuations in the CMB for a $Λ$CDM universe. We contend that only distance-estimators as accurate as SBF are able settle the question of whether the CMB dipole arises from the gravitational influence of large-scale structure within, or without $\sim$100 Mpc of the Local Group.

2604.00525 2026-05-11 hep-lat cond-mat.stat-mech math-ph math.MP

Strong-coupling expansion and two-point Padé approximation for lattice $ϕ^4$ field theory

Yuanran Zhu, Efekan Kökcü, Chao Yang

AI总结 该研究针对格点 $ϕ^4$ 场论中中等及强耦合下的关联函数近似难题,提出了一种结合弱耦合和强耦合展开的两重点Padé逼近方法。该方法能够在广泛的耦合范围内提供高精度的两点关联函数近似,优于传统的单点重求和方法。研究还分析了该方法的收敛行为及其适用范围,为量子场论中的非微扰计算提供了新的有效工具。

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Reliable approximations for correlation functions at intermediate and strong coupling remain hard to obtain for general quantum field theories. Perturbative expansions are often asymptotic or have a finite radius of convergence, which limits their applicability beyond weak coupling. Here we combine weak- and strong-coupling expansions and propose to use two-point Padé schemes to construct approximants. For lattice $ϕ^4$ theory, we show that this two-point interpolation strategy yields accurate global approximations to the two-point correlation function across broad coupling regimes and compares favorably with standard one-point resummation methods. We also provide heuristic explanations for the observed convergence behavior and discuss the practical range of validity of the approach.

2603.29091 2026-05-11 hep-lat quant-ph

Ether of Orbifolds

Henry Lamm

AI总结 本文研究了使用“轨道折叠晶格”对杨-米尔斯理论进行量子模拟的可行性,指出其声称的指数级加速优势在定量分析下并不成立。通过解析推导、蒙特卡洛模拟和电路构造,作者发现了轨道折叠方法中特有的代价问题,包括质量依赖的 Trotter 误差、非单态污染以及必须进行的质量外推。研究结果表明,对于典型规模的计算,轨道折叠方法相比现有其他方法效率低几个数量级,因此其宣称的计算优势无法经受住定量检验。

Comments 7+2 pages, 1 figure. Clarified confusion meaning of gauge invariance, Additional acknowledgments

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The orbifold lattice has been proposed as a route to practical quantum simulation of Yang--Mills theory, with claims of exponential speedup over all known approaches. Through analytical derivations, Monte Carlo simulation, and explicit circuit construction, we identify compounding costs entirely absent in Kogut--Susskind formulations: a mass-dependent Trotter overhead that scales as $m^4$, non-singlet contamination that grows as $m^2$ and worsens with penalty terms, and a mandatory mass extrapolation. Monte Carlo simulations of SU(3) establish a universal scaling: the continuum limit forces $m^2 \propto 1/a$, binding the Trotter step to the lattice spacing through a cost unique to orbifolds. For a fiducial $10^3$ calculation, the orbifold is $10^4$--$10^{10}$ times more expensive than every published alternative. These results indicate that the claimed computational advantages do not at present survive quantitative scrutiny.

2603.25806 2026-05-11 stat.ME math.ST stat.CO stat.TH

Context Tree Prior Distributions based on Node Weighting with exact Bayes Factors

Thiago Paulichen, Victor Freguglia

AI总结 该研究提出了一种基于节点加权的上下文树先验分布方法,用于构建变量长度马尔可夫链(VLMC)模型。通过在节点上直接指定权重函数,该方法能够直观地将结构假设融入先验分布,克服了传统分支过程方法在结构控制方面的局限性。研究还引入了精确的贝叶斯因子计算方法,支持模型比较与假设检验,并展示了该方法在模拟研究中的灵活性与有效性。

Comments 31 pages, 9 figures

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Variable-length Markov chains (VLMCs) are a flexible class of higher-order Markov models that admit a natural representation as context trees. Existing Bayesian methods for specifying prior distributions on tree structures rely on branching processes, but these suffer from a fundamental limitation. The connection between branching probabilities at individual nodes and the structural properties of the induced tree distribution is not straightforward, making it difficult to construct priors encoding specific structural beliefs. We address this limitation by introducing a novel representation of prior distributions on tree space based on context-tree functions. By directly specifying weights for individual contexts through a function on nodes, our approach provides an intuitive mechanism for incorporating structural hypotheses into the prior. This class of distributions maintains computational tractability, allowing marginal likelihoods and posterior mode trees to be computed exactly via generalizations of the Context Tree Weighting (CTW) and Context Tree Maximizing (CTM) algorithms. Exact Bayes factor computation enables rigorous model comparison and hypothesis testing. We demonstrate the flexibility and effectiveness of our approach through simulation studies comparing different prior specifications, and develop practical algorithms for selecting the maximal depth and performing model selection based on Bayes factors.

2603.25774 2026-05-11 quant-ph

Catalytic Quantum Error Correction: Theory, Efficient Catalyst Preparation, and Numerical Benchmarks

Hikaru Wakaura, Taiki Tanimae

AI总结 量子计算机面临环境噪声的挑战,传统量子纠错方法在噪声超过一定阈值时失效。本文提出了一种新的量子纠错方法——催化量子纠错(CQEC),通过催化相干性放大实现无阈值纠错,在多种噪声强度下保持高保真度。研究还展示了高效的催化子制备方案,大幅降低所需噪声副本数量,为表面码处理器中的辅助模块修复提供了新途径。

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Quantum computers promise transformative speedups, but environmental noise destroys their fragile states. Conventional quantum error correction (QEC) encodes information redundantly across physical qubits, yet fails above a threshold of about $1\%$ and incurs polynomial qubit overhead. A recent theorem [Shiraishi2024] from the resource theory of coherence shows that catalytic covariant operations amplify coherence at an unbounded rate, but this result has never been cast as an operational protocol. The challenge is to turn an asymptotic theorem into a recovery scheme that works at any noise strength with realistic resources. Here we show that catalytic coherence amplification can be cast as an error-correction primitive, Catalytic Quantum Error Correction (CQEC), which recovers a known target state from noisy copies without any error \emph{magnitude} threshold whenever the target's coherent modes are preserved. Whereas existing QEC degrades above its threshold, CQEC maintains $F > 0.999$ across 200~configurations spanning $d = 4$--$64$, and the impractical $n^{*} \sim d^{4} e^{2γ}$ copy requirement is reduced by nine orders of magnitude via a three-stage pipeline combining CPMG dynamical decoupling, Clifford twirling, and recursive swap-test purification, yielding $F_\mathrm{cat} > 0.96$ from only eight noisy copies. These results turn an abstract resource-theoretic statement into a concrete tool complementary to stabilizer- and purification-based QEC. By replacing a quantitative threshold with a qualitative condition on the support of coherence, CQEC enables ancillary modules within surface-coded processors to be repaired far beyond the conventional threshold; an open-source package reproducing all results in $\sim$30\,s accompanies this work (arXiv:2603.25774, https://github.com/deeptell-inc/cqec).

2603.19791 2026-05-11 cs.CR

Text-Based Personas for Simulating User Privacy Decisions

Kassem Fawaz, Ren Yi, Octavian Suciu, Rishabh Khandelwal, Hamza Harkous, Nina Taft, Marco Gruteser

AI总结 该研究旨在模拟人类隐私决策行为,以支持自主代理与个体意图的对齐以及高效开展隐私相关的用户研究。为解决现有方法在个体准确性、可审计性、计算效率和群体代表性之间的平衡问题,作者提出了一种基于文本生成的合成隐私人物设定方法Narriva,该方法基于用户过往隐私决策数据而非刻板的人口统计特征进行建模。实验表明,该方法在多个数据集上实现了高达87%的预测准确率,并显著减少了提示词数量,同时能够复现不同研究中的隐私行为模式。

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The ability to simulate human privacy decisions has significant implications for aligning autonomous agents with individual intent and conducting cost-effective, large-scale privacy-centric user studies. Prior approaches prompt Large Language Models (LLMs) with natural language user statements, data-sharing histories, or demographic attributes to simulate privacy decisions. These approaches, however, fail to balance individual-level accuracy, human auditability, token efficiency, and population-level representation. We present Narriva, an approach that generates text-based synthetic privacy personas to address these shortcomings. Narriva grounds persona generation in prior user privacy decisions, such as those from large-scale survey datasets, rather than purely relying on demographic stereotypes. It compresses this data into concise, human-readable summaries structured by established privacy theories. Through benchmarking across five diverse datasets, we analyze the characteristics of Narriva's synthetic personas in modeling both individual and population-level privacy preferences. We find that grounding personas in past privacy behaviors achieves up to 87% predictive accuracy, improving over a non-personalized LLM baseline by 6-17 percentage points across datasets, while yielding an 80-95% reduction in prompt tokens compared to in-context learning with raw examples. Finally, we demonstrate that personas synthesized from a single survey can reproduce the aggregate privacy behaviors and statistical distributions of entirely different studies.

2603.17736 2026-05-11 quant-ph cs.DS

Optimal detection of dissipation in Lindbladian dynamics

Yiyi Cai

AI总结 本文研究了如何通过观测量子系统的时间演化过程,判断其动力学是否受到环境引起的耗散噪声影响。作者提出了一种随机算法,能够在总演化时间为 $\mathcal{O}(ε^{-1})$ 的情况下,判断由未知 Lindbladian 生成的动力学是否为纯哈密顿型或包含至少大小为 $ε$ 的耗散项,该时间复杂度在信息论上是最佳的。该方法在 Lindbladian 生成元强度有界、耗散部分具有常数局域性和有界度数的假设下有效,为实验中检测量子动力学中的耗散噪声提供了实用手段。

Comments 30 pages; v2 fixes errors in analysis and updates technical overview

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Experimental implementations of Hamiltonian dynamics are often affected by dissipative noise arising from interactions with the environment. This raises the question of whether one can detect the presence or absence of such dissipation using only access to the observed time evolution of the system. We consider the following decision problem: given black-box access to the time-evolution channels $e^{t\mathcal{L}}$ generated by an unknown time-independent Lindbladian $\mathcal{L}$, determine whether the dynamics are purely Hamiltonian or contain dissipation of magnitude at least $ε$ in normalized Frobenius norm. We give a randomized procedure that solves this task using total evolution time $\mathcal{O}(ε^{-1})$, which is information-theoretically optimal. This guarantee holds under the assumptions that the Lindblad generator has bounded strength and its dissipative part is of constant locality with bounded degree. Our work provides a practical method for detecting dissipative noise in experimentally implemented quantum dynamics.

2603.16246 2026-05-11 quant-ph

Tunable Rotation-Associated Slow-to-Fast Light Conversion via Optomagnonic Coupling

Jingyu Liu, Shirong Lin

AI总结 该研究通过引入磁子自由度构建了一个集成光子、声子和磁子的光磁系统,解决了传统光力学系统中机械频率固定导致的可调性受限问题。研究提出了光磁-拉盖尔-高斯旋转系统的理论模型,并通过数值模拟展示了法诺共振和群延迟现象,实现了与磁子和机械旋转相关的可调光速转换。该工作不仅拓展了光速转换的频率范围,还通过连续控制场频率调制实现了双向光速转换,并展示了多频率下光速动态切换的可行性,为全光网络和量子通信提供了灵活的调控平台。

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Cavity optomechanics has enabled slow-to-fast light conversion, but traditional optomechanic systems suffer from limited tunability due to fixed mechanical frequencies. To address this constraint, we introduce a magnon degree of freedom into an optomechanical system, constructing a system that integrates photons, phonons, and magnons. We establish the theoretical model of the optomagnonic-Laguerre-Gaussian rotational system, and present numerical simulations of Fano resonances and group delay. By manipulating the magnon degree of freedom, we not only achieve slow-to-fast light conversion associated with magnons but also successfully realize such conversion effects associated with mechanical rotation-this achievement effectively overcomes the inherent tunability limitations of pure optomechanical systems and expands the frequency coverage of light conversion effects. Notably, we numerically demonstrate bidirectional light speed conversion (slow-to-fast and fast-to-slow) via continuous control field frequency modulation to tune cavity mode detuning. Additionally, our results show that adjusting optomagnonic parameters enables dynamic switching between slow light and fast light at multiple frequencies. This work provides a flexible platform for multi-frequency light speed control, with potential applications in all-optical networks and quantum communications.

2603.10236 2026-05-11 cs.LO

Extending CDCL-based Model Enumeration with Weights

Giuseppe Spallitta, Moshe Y. Vardi

AI总结 本文研究了带权重的模型枚举(WME)问题,即在给定布尔公式及其满足赋值的权重函数时,按权重进行模型枚举。为解决该问题,作者提出了一种基于CDCL的算法,融合了权重传播、基于权重的剪枝和权重感知的冲突分析,分别应用于时序回溯和非时序回溯框架。实验表明,两种方法各有优势,适用于不同场景,为处理带权重的模型枚举提供了有效且互补的解决方案。

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In this work we investigate Weighted Model Enumeration (WME): given a Boolean formula and a weight function over its satisfying assignments, enumerate models while accounting for their weights. This setting supports weight-driven queries, such as producing the top-k models or all models above a threshold. While related to AllSAT, Weighted Model Counting, and MaxSAT, these paradigms do not treat selective enumeration under weights as a native solver task. We present CDCL-based algorithms for WME that integrate weight propagation, weight-based pruning, and weight-aware conflict analysis into both chronological and non-chronological backtracking frameworks. Chronological backtracking exploits implicit blocking and keeps the clause database compact, thereby reducing memory footprint and enabling efficient propagation. In contrast, non-chronological backtracking with clause learning supports explicit blocking and restarts. We show that both approaches are feasible and complementary, highlighting trade-offs in pruning effectiveness with weights and clarifying when each performs best.

2603.08811 2026-05-11 physics.flu-dyn

Experimental Challenges in Determining Heat Transfer Efficiency Scaling in Highly Turbulent Cryogenic Rayleigh-Benard Convection

P. Urban, V. Musilova, P. Hanzelka, T. Kralik, M. Macek, L. Skrbek

AI总结 该研究探讨了在极高雷诺数下通过低温氦实验研究瑞利-贝纳德对流热传递效率标度时面临的实验挑战。研究分析了实验不确定性及数据修正方法,包括绝热温度梯度、寄生热泄漏和有限热导率等影响因素,并针对布拉格圆柱形对流腔实验中的测量误差、工作点选择及流体物性参数评估进行了详细讨论。研究强调了严格不确定性分析在区分对流最终态转变与非奥伯贝克-布森奎斯效应及实验缺陷影响中的重要性。

Comments 19 pages, 9 figures. Submitted to Journal of Low Temperature Physics

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Cryogenic Rayleigh-Benard convection (RBC) at very high Rayleigh numbers (Ra) serves as a key system for understanding buoyancy-driven industrial and large scale natural flows and for testing theories of turbulent convective heat transport. Cryogenic helium experiments allow one to reach extremely high Ra under well-controlled laboratory conditions; however, interpretation of the resulting heat-transfer scalings remains sensitive to non-Oberbeck-Boussinesq (NOB) effects, experimental uncertainties, as well as a number of corrections that ought to be applied to raw data, including corrections for the adiabatic temperature gradient, parasitic heat leaks, or finite thermal conductivity of plates and sidewalls of RBC cells. We present an analysis of experimental uncertainties and data corrections procedures applicable to cryogenic RBC experiments, specifically to those performed in cylindrical RBC cells in Brno: measurement uncertainties, parasitic effects, choice of 4He working points in the p-T diagram and evaluation of relevant properties of the particular working fluid in connection with the available thermophysical property databases. In particular, our study highlights the necessity of rigorous uncertainty analysis for assessing experimental evidence suggesting either transition to the ultimate regime of RBC due to intrinsic ultimate-regime dynamics or as a manifestation of NOB effects and experimental imperfections.

2603.08720 2026-05-11 cs.AR cs.ET

AnalogToBi: Device-Level Analog Circuit Topology Generation via Bipartite Graph and Grammar Guided Decoding

Seungmin Kim, Mingun Kim, Yuna Lee, Yulhwa Kim

AI总结 本文提出了一种名为AnalogToBi的框架,用于生成器件级别的模拟电路拓扑结构。该方法通过引入双图表示和语法引导解码,提升了结构泛化能力和电路有效性,同时采用器件重命名增强等技术减少对训练数据的记忆。实验表明,AnalogToBi在无需人工干预的情况下能够生成高有效性和新颖性的电路拓扑。

Comments 20 pages, 8 figures

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Analog circuit design remains highly dependent on expert knowledge due to the complexity of device-level interactions and topology design. Recent transformer-based approaches for device-level topology generation have shown promise, yet they suffer from low electrical validity without human-in-the-loop (HITL) training and severe memorization caused by sequence-based circuit representations. In this work, we propose AnalogToBi, a framework for device-level analog circuit topology generation. AnalogToBi introduces circuit-type conditioning for categorizing heterogeneous multi-type topology datasets, device renaming augmentation to mitigate memorization, a bipartite graph representation for improved structural generalization, and grammar-guided decoding to enforce structural validity during bipartite graph generation. Experimental results demonstrate that AnalogToBi achieves high validity and novelty without HITL training while effectively avoiding memorization of training topologies. Our code is available at https://github.com/Seungmin0825/AnalogToBi.

2603.07620 2026-05-11 astro-ph.HE

A jet formation model for astrophysical objects

Chun Xu

AI总结 本文提出了一种适用于活动星系核、年轻恒星天体和X射线双星的统一喷流形成模型。该模型认为吸积盘释放的结合能主要以湍流形式储存,而非通过辐射耗散,从而形成以对流为主导的吸积流。在中心天体附近,湍流中最小的稳定团块通过速度分布和角动量守恒机制加速至逃逸速度以上,最终通过类似漏斗的结构形成两股对向喷流。研究指出喷流的形成与湍流中储存的能量比例参数η密切相关,且η需大于0.5才能形成喷流。

Comments 1 figure, 7 pages; resubmitted to MNRAS after major revision

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We propose a unified model for jet formation applicable to active galactic nuclei, young stellar objects, and X-ray binaries. In this model, the binding energy released from the accretion disk is primarily stored as turbulence rather than being radiated away, leading to the formation of advection-dominated accretion flows. Near the central object, a thick accretion disk with funnel-like structures develops. Within the turbulent flows, the smallest stable blobs can be accelerated beyond the escape velocity through the combination of two mechanisms - the Gaussian-like velocity distribution within the turbulence and a mechanism involving the combined effects of inward pressure force and angular momentum conservation.These rapidly moving blobs may exit through the funnels, collectively forming two opposing jets. This model predicts that jets originate from the innermost region of the thick disk surrounding the central object. The formation of jet is directly related a parameter ηthat describes the energy fraction stored in turbulence in units of the binding energy of local Keplerian energy. η> 0.5 is a minimal condition for jet to form. This model can be extended to account for jet formation in active galactic nuclei, young stellar objects, X-ray binaries, and other analogous astronomical systems.

2603.05363 2026-05-11 eess.SY cs.SY

Comprehensive Approach to Directly Addressing Estimation Delays in Stochastic Guidance

Liraz Mudrik, Yaakov Oshman

AI总结 在实际的追逃场景中,目标的突发机动会导致估计延迟,进而影响拦截性能。本文提出了一种综合策略,通过引入基于粒子的固定滞后平滑器和半马尔可夫模型,显式处理时变估计延迟问题,实现了估计、延迟建模与引导的统一框架。该方法能够实时估计延迟并自适应调整引导输入,实验表明其在鲁棒性和有效性方面优于现有方法。

Comments Submitted to journal publication. 48 pages, 12 figures

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In realistic pursuit-evasion scenarios, abrupt target maneuvers generate unavoidable periods of elevated uncertainty that result in estimation delays. Such delays can degrade interception performance to the point of causing a miss. Existing delayed-information guidance laws fail to provide a complete remedy, as they typically assume constant and known delays. Moreover, in practice they are fed by filtered estimates, contrary to these laws' foundational assumptions. We present an overarching strategy for tracking and interception that explicitly accounts for time-varying estimation delays. We first devise a guidance law that incorporates two time-varying delays, thereby generalizing prior deterministic formulations. This law is driven by a particle-based fixed-lag smoother that provides it with appropriately delayed state estimates. Furthermore, using semi-Markov modeling of the target's maneuvers, the delays are estimated in real-time, enabling adaptive adjustment of the guidance inputs during engagement. The resulting framework consistently conjoins estimation, delay modeling, and guidance. Its effectiveness and superior robustness over existing delayed-information guidance laws are demonstrated via an extensive Monte Carlo study.

2603.04824 2026-05-11 cond-mat.mtrl-sci

Design rules for industrial-scale sintering of UB4-UBC composites with high uranium density

Riley Moeykens, Anthony Albert-Harrup, David Simonne, Mehmet Topsakal, Ericmoore Jossou

AI总结 该研究探讨了高铀密度UB₄-UBC复合材料在工业规模烧结中的设计规则。通过工业可扩展的硼碳热还原法合成UB₄和UBC复合材料,并利用原位同步辐射X射线衍射研究其高温结构演变,结合热重分析评估氧化行为,结果表明UB₄-UBC复合材料相比单一UB₄具有更高的铀负载和更优异的高温氧化性能,显示出作为先进核燃料的潜力。

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英文摘要

Uranium borides are promising candidate fuel forms for use in advanced nuclear reactors due to their high thermal conductivity and potential for dual use as both fuel and burnable absorber materials. In this work, uranium tetraboride (UB$_4$) and uranium monoboroncarbide (UBC) composites were synthesized using an industrially scalable borocarbothermic reduction method. The high-temperature structural evolution of the as-synthesized borides was investigated using in situ synchrotron X-ray diffraction (SXRD). The oxidation behavior was further characterized using a combination of SXRD and thermogravimetric analysis (TGA), allowing direct comparison with other potential accident-tolerant fuels such as UB$_2$, U$_3$Si$_2$, UC, and UN. The UB$_4$-UBC composite shows higher uranium loading than monolithic UB$_4$ and demonstrates promising oxidation behavior at elevated temperature, pointing to its potential as an improved uranium boride-based fuel form.