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The detection, extraction and parameter estimation of extreme-mass-ratio inspirals with deep learning

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Science China(physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 86-96页

作者： Qianyun Yun Wen-Biao Han Yi-Yang Guo He Wang Minghui Du Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences School of physics and Astronomy Shanghai Jiao Tong University School of Astronomy and Space Science University of Chinese Academy of Sciences Taiji Laboratory for Gravitational Wave Universe (Beijing/Hangzhou) University of Chinese Academy of Sciences Lanzhou center for Theoretical physics Key Laboratory of Theoretical Physics of Gansu Province Key Laboratory of Quantum Theory and Applications of MoE Lanzhou University Institute of Theoretical physics & Research center of Gravitation Lanzhou University International Centre for Theoretical physics Asia-Pacific (ICTP-AP) University of Chinese Academy of Sciences (UCAS) center for Gravitational Wave Experiment National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences

One of the primary goals of space-borne gravitational wave detectors is to detect and analyze extreme-mass-ratio inspirals(EMRIs). This task is particularly challenging because EMRI signals are complex, lengthy, and faint. In this work, we introduce a2-layer convolutional neural network(CNN) approach to detect EMRI signals for space-borne detectors, achieving a true positive rate(TPR) of 96.9% at a 1% false positive rate(FPR) for signal-to-noise ratio(SNR) from 50 to 100. Especially, the key intrinsic parameters of EMRIs such as the mass, spin of the supermassive black hole(SMBH) and the initial eccentricity of the orbit can also be inferred directly by employing a neural network. The mass and spin of the SMBH can be determined at 99% and 92% respectively. This will greatly reduce the parameter spaces and computing cost for the following Bayesian parameter *** model also has a low dependency on the accuracy of the waveform model. This study underscores the potential of deep learning methods in EMRI data analysis, enabling the rapid detection of EMRI signals and efficient parameter estimation.

关键词： gravitational wave EMRIs deep-learing

All-optical neuromorphic devices: materials, working mechanism,and applications

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Science China Chemistry 2025年

作者： Song Wang Hao Chen Hui Huang College of Materials Science and Opto-Electronic Technology Center of Materials Science and Optoelectronics Engineering CAS Center for Excellence in Topological Quantum Computation CAS Key Laboratory of Vacuum Physics University of Chinese Academy of Sciences College of Chemistry and Molecular Engineering Peking University

Traditional von Neumann computing, with physical separation of memory and processing units, cannot satisfy the development of artificial intelligence and cloud computing. Neuromorphic computing, inspired by the human brain, has drawn much ***-optical neuromorphic (AON) devices employ optical signals as information carriers and leverage the neuromorphic functions to implement fast operation speed, low energy consumption, and high bandwidth of neuromorphic computing. Here, we discuss the recent progress in AON devices, including materials, device performance, working mechanisms, and applications. Moreover,the advantages and limitations of AON are presented and discussed. Finally, the perspective of AON devices points out the future research direction of neuromorphic computing.

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Optical study on intermediate-valence compounds Yb_(1-x)Lu_xAl_3

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Chinese physics B 2018年第1期27卷 209-214页

作者：吕佳林雒建林王楠林 Institute of physics Chinese Academy of Sciences School of Physical sciences University of Chinese Academy of Sciences Collaborative Innovation center of quantum Matter International center for quantum Materials School of Physics Peking University

We report an optical spectroscopy study on intermediate valence system Ybl-xLuxA13 with x = 0, 0.25, 0.5, 0.75, and 1. The Kondo temperature in the system is known to increase with increasing Lu concentration. Therefore, it is expected that the energy scale of the hybridization gap should increase with increasing Lu concentration based on the periodic Anderson model. On the contrary, we find that the spectral structure associated with the hybridization effect shifts monotonically to lower energy. Furthermore, the Lu substitution results in a substantial increase of the free carrier spectral weight and less pronounced plasma frequency reduction upon lowering temperature. We attribute the effect to the disruption of the Kondo lattice periodicity by the random substitution of Yb by Lu. The work highlights the importance of the lattice periodicity of the rare earth element for understanding the Kondo lattice phenomena.

关键词： heavy fermions intermediate valence system optical conductivity hybridization effect

Majorana Representation and Mean Field Approach for Interacting-Boson System

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Communications in Theoretical physics 2017年第10期67卷 439-446页

作者：刘昊迪方杰郑泰玉 center for quantum sciences and School of physics Northeast Normal University

The Majorana representation, which represents a quantum state by stars on the Bloch sphere, provides us an intuitive tool to study the quantum evolution in high dimensional Hilbert space. In this work, we investigate the second quantized model and the mean-field model for the interacting-boson system in the Majorana representation. It is shown that the motions of states in the two models are same in the linear case. Furthermore, the contribution of the nonlinear interaction to the star motions in the second quantized model can be expressed by a single star part which is equal to the nonlinear part of the equation for the star in mean-field model under large boson number limit and an extra part caused by the correlation between stars. These differences and relations can not only be reflected by the population differences between the two boson modes in the two models, but also lie with the differences between the continuous changes of the second quantized evolution with the nonlinear interacting strength and the critical behavior of the mean-field evolution which related to the self-trapping effect. The reason of the difference between the two models is also discussed by an effective Hamiltonian.

关键词： Majorana representation mean-field approach interacting-boson system

Superconductivity in topological semimetals

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National Science Review 2019年第2期6卷 199-202页

作者： Jian Wang International center for quantum Materials School of Physics Peking University Collaborative Innovation center of quantum Matter CAS center for Excellence in Topological quantum Computation University of Chinese Academy of Sciences Beijing Academy of quantum Information sciences

Topological superconductors, where the bulk state shows superconducting gap and Majorana fermions constitute gapless edge states, have become one of the most important topics in physical sciences. Majorana fermions are their own antiparticles and Majorana quasiparticles in a solid-state system obey non-Abelian statistics, and thus can be used for faulttolerant topological quantum computation.

关键词： As Superconductivity in topological semimetals

Three-dimensional spin–orbit coupled Fermi gases:Fulde–Ferrell pairing, Majorana fermions, Weyl fermions,and gapless topological superfluidity

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Chinese physics B 2015年第5期24卷 44-55页

作者： Xia-Ji Liu Hui Hu Han Pu center for quantum and Optical Science Swinburne University of Technology Department of physics and Astronomy and Rice Quantum Institute Rice University center for Cold Atom physics Chinese Academy of Sciences

We theoretically investigate a three-dimensional Fermi gas with Rashba spin-orbit coupling in the presence of both out-of-plane and in-plane Zeeman fields. We show that, driven by a sufficiently large Zeeman field, either out-of-plane or in-plane, the superfluid phase of this system exhibits a number of interesting features, including inhomogeneous Fulde- Ferrell pairing, gapped or gapless topological order, and exotic quasi-particle excitations known as Weyl fermions that have linear energy dispersions in momentum space （i.e., massless Dirac fermions）. The topological superfluid phase can have either four or two topologically protected Weyl nodes. We present the phase diagrams at both zero and finite temperatures and discuss the possibility of their observation in an atomic Fermi gas with synthetic spin-orbit coupling. In this context, topological superfluid phase with an imperfect Rashba spin-orbit coupling is also studied.

关键词： Fulde-Ferrell superfluid topological superfluid spin-orbit coupling

Variable Coupling Strength of Silicene on Ag(lll)

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Chinese physics Letters 2015年第3期32卷 124-127页

作者：冯宝杰黎文彬邱静岚程鹏陈岚陈岚吴克辉 Institute of physics Chinese Academy of Sciences Collaborative Innovation center of quantum Matter

We perform a scanning tunneling microscopy and spectroscopy study on the electronic structures of √3×√3- silicene on Ag（111）. It is found that the coupling strength of √3×√3-silicene with the Ag-（111） substrate is variable in different regions, giving rise to notable effects in experiments. This evidence of decoupling or variable interaction of silicene with the substrate is helpful to in-depth understanding of the structure and clectronic properties of silieene.

关键词： Variable Coupling Strength of Silicene on Ag lll

Topological Phase in Non-centrosymmetric Material NaSnBi

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Chinese physics Letters 2016年第12期33卷 115-119页

作者：代霞勒聪聪吴贤新秦盛山林志萍胡江平 Institute of physics Chinese Academy of Sciences Collaborative Innovation center of quantum Matter

We predict that a non-eentrosymmetric material NaSnBi locates in a three-dimensional non-trivial topological phase under ambient pressure based on first-principle calculations. By deriving the effective model around the Г point, we find that the topological phase transition is driven by a Rashba spin-orbital coupling through an odd number of pairs of band touch due to a small anisotropic gap caused by quintie dispersion terms. In contrast to conventional topological insulators, the spin texture of the surface Dirac cone is right-handed and the surface states are strikingly different for different surface terminations.

关键词： of on as in for is that

Effect of Terraces at the Interface on the Structural and Physical Properties of La_(0.8)Sr_(0.2)MnO_3 Thin Films

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Chinese physics Letters 2016年第7期33卷 124-128页

作者：冯雅晴金奎娟葛琛何旭谷林杨振中郭海中万骞何萌吕惠宾杨国桢 Institute of physics Chinese Academy of Sciences Collaborative Innovation center of quantum Matter

Employing atomic force microscopy, transmission electron microscopy and the second harmonic generation tech- nique, we carefully explore the structural properties of 6-unit-cell-thick La0.8Sr0.2 MnO3 films grown on SrTiO3 with atomically fiat TiO2-terminated terraces on the surface. The results clearly demonstrate that the terraces on the surface of TiO2-terminated SrTiO3 can improve the layer-by-layer epitaxial growth of the manganite films, which results in uniform film coverage at the beginning of growth and thus reduces the substrate-induced disorder at or near the interface. Comparing the magnetic and transport properties of La0.8Sr0.2NlnO3 films with the thicknesses varying from 6 unit cells to 80 unit cells grown respectively on as-received SrTi03 and TiO2- terminated SrTiO3, it is found that these atomically flat terraces on the surface of TiO2-terminated SrTiO3 can greatly enhance the Curie temperature and conductivities of the ultrathin La0.8Sr0.2MnO3 films with thickness less than 50 unit cells, while no obvious difference is detected in the magnetic and transport properties of the 80 unit-cell thick films.

关键词： STO in of on LSMO Sr