Science China Physics, Mechanics & Astronomy最新文献_第7页

Measuring the anisotropies in astrophysical and cosmological gravitational-wave backgrounds with Taiji and LISA networks 利用太极和 LISA 网络测量天体物理学和宇宙学引力波背景中的各向异性

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-10-24 DOI: 10.1007/s11433-024-2498-0

Zhi-Chao Zhao, Sai Wang

引用次数: 0

Re-emergence of superconductivity via pressure-induced Lifshitz transition in preserved 6R-TaS2 crystal structure 在保留的 6R-TaS2 晶体结构中通过压力诱导的 Lifshitz 转变重新出现超导电性

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-10-24 DOI: 10.1007/s11433-024-2476-4

Xindeng Lv, Hao Song, Kun Chen, Sirui Liu, Yanping Huang, Yuqiang Fang, Zexiang Shen, Tian Cui

{"title":"Re-emergence of superconductivity via pressure-induced Lifshitz transition in preserved 6R-TaS2 crystal structure","authors":"Xindeng Lv, Hao Song, Kun Chen, Sirui Liu, Yanping Huang, Yuqiang Fang, Zexiang Shen, Tian Cui","doi":"10.1007/s11433-024-2476-4","DOIUrl":"10.1007/s11433-024-2476-4","url":null,"abstract":"<div>Investigating the implications of interlayer coupling on superconductivity is vital for comprehending the intrinsic mechanisms of two-dimensional materials. Van der Waals heterojunctions have attracted extensive research owing to their exotic interlayer coupling. In this study, we investigated the natural heterostructure superconductor featuring 6R-TaS2 via measurements of electrical resistance, the Hall effect, and in-situ synchrotron X-ray diffraction (XRD) under various pressures. The study findings show that the superconducting transition temperature (Tc) of 6R-TaS2 in the range of 0–32.5 GPa exhibits an unusual double-dome behavior as a function of pressure, with the first and second domes in the pressure range of 0–5.3 and 6.8–32.5 GPa, respectively. At 56.6 GPa, a new superconducting phase with a Tc of 2 K was observed. The XRD results show that the singular evolution of the Tc is independent of the structural phase transition. Combining the XRD results, first-principles calculations, and Hall effect measurements, we found that different interlayer coupling effects resulted in double dome superconductivity and the re-emergence of superconducting. Our findings shed light on the pivotal role of interlayer coupling in driving the anomalous alterations in superconducting properties triggered by charge transfer and Fermi surface reconstruction and provide an alternative route for comprehending the mechanisms of superconductivity in transition metal dichalcogenides (TMDs).</div>","PeriodicalId":774,"journal":{"name":"Science China Physics, Mechanics & Astronomy","volume":"67 12","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142518582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Statistics and dynamics of coherent structures in compressible wall-bounded turbulence 可压缩壁界湍流中相干结构的统计与动力学

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-10-24 DOI: 10.1007/s11433-024-2481-8

Ming Yu, SiWei Dong, XianXu Yuan, ChunXiao Xu

引用次数: 0

Non-Hermitian polarization quantized by time-reversal symmetry 通过时间反转对称量化的非赫米极化

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-10-23 DOI: 10.1007/s11433-024-2484-0

Jing Cheng, Jinbing Hu, Zhigao Hu, Lin Chen, Minghui Lu, Songlin Zhuang

引用次数: 0

Investigating the neutron star physics through observations of several young pulsars in the dipole-field re-emergence scenario 通过观测偶极子场重现情景下的几颗年轻脉冲星研究中子星物理学

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-10-23 DOI: 10.1007/s11433-024-2473-6

Yu-Long Yan, Quan Cheng, Xiao-Ping Zheng

{"title":"Investigating the neutron star physics through observations of several young pulsars in the dipole-field re-emergence scenario","authors":"Yu-Long Yan, Quan Cheng, Xiao-Ping Zheng","doi":"10.1007/s11433-024-2473-6","DOIUrl":"10.1007/s11433-024-2473-6","url":null,"abstract":"<div>The observed timing data, magnetic tilt angle χ, and age of young pulsars could be used to probe some important issues about neutron star (NS) physics, e.g., the NS internal magnetic field configuration, and the number of precession cycles ξ. Both quantities are critical in studying the continuous gravitational wave emission from pulsars, and the latter generally characterizes the mutual interactions between superfluid neutrons and other particles in the NS interior. The timing behavior of pulsars can be influenced by the dipole field evolution, which instead of decaying, may increase with time. An increase in the dipole field may result from the re-emergence of the initial dipole field Bd,i that was buried into the NS interior shortly after the birth of the NS. In this work, the field re-emergence scenario ξ and the internal field configuration of several young pulsars, as well as their Bd,i are investigated by assuming typical accreted masses ΔM. Moreover, since the Crab pulsar has an exactly known age and its tilt angle change rate can be inferred from observations, we can set stringent constraints on its ξ, Bd,i, and ΔM. Although for other young pulsars without exactly known ages and tilt angle change rates, these quantities cannot be accurately determined, we find that their ξ are generally within ∼104–106, and some of them probably have magnetar-strength Bd,i. Our work could be important for investigating the transient emissions associated with NSs, the origin of strong magnetic fields of NSs, pulsar population, continuous gravitational wave emission from pulsars, and accretion under extreme conditions in principle.</div>","PeriodicalId":774,"journal":{"name":"Science China Physics, Mechanics & Astronomy","volume":"67 12","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142519088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Gravitational wave search by time-scale-recursive denoising and matched filtering 利用时标递归去噪和匹配滤波搜索引力波

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-10-23 DOI: 10.1007/s11433-024-2469-4

Cunliang Ma, Chenyang Ma, Zhoujian Cao, Mingzhen Jia

{"title":"Gravitational wave search by time-scale-recursive denoising and matched filtering","authors":"Cunliang Ma, Chenyang Ma, Zhoujian Cao, Mingzhen Jia","doi":"10.1007/s11433-024-2469-4","DOIUrl":"10.1007/s11433-024-2469-4","url":null,"abstract":"<div>In our previous work [Physical Review D, 2024, 109(4): 043009], we introduced MSNRnet, a framework integrating deep learning and matched filtering methods for gravitational wave (GW) detection. Compared with end-to-end classification methods, MSNRnet is physically interpretable. Multiple denoising models and astrophysical discrimination models corresponding to different parameter space were operated independently for the template prediction and selection. But the MSNRnet has a lot of computational redundancy. In this study, we propose a new framework for template prediction, which significantly improves our previous method. The new framework consists of the recursive application of denoising models and waveform classification models, which solve the problem of computational redundancy. The waveform classification network categorizes the denoised output based on the signal’s time scale. To enhance the denoising performance for long-time-scale data, we upgrade the denoising model by incorporating Transformer and ResNet modules. Furthermore, we introduce a novel training approach that allows for the simultaneous training of the denoising network and waveform classification network, eliminating the need for manual annotation of the waveform dataset required in our previous method. Real-data analysis results demonstrate that our new method decreases the false alarm rate by approximately 25%, boosts the detection rate by roughly 5%, and slashes the computational cost by around 90%. The new method holds potential for future application in online GW data processing.</div>","PeriodicalId":774,"journal":{"name":"Science China Physics, Mechanics & Astronomy","volume":"67 12","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142540690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An efficient quantum proactive incremental learning algorithm 高效量子主动增量学习算法

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-10-22 DOI: 10.1007/s11433-024-2501-4

Lingxiao Li, Jing Li, Yanqi Song, Sujuan Qin, Qiaoyan Wen, Fei Gao

{"title":"An efficient quantum proactive incremental learning algorithm","authors":"Lingxiao Li, Jing Li, Yanqi Song, Sujuan Qin, Qiaoyan Wen, Fei Gao","doi":"10.1007/s11433-024-2501-4","DOIUrl":"10.1007/s11433-024-2501-4","url":null,"abstract":"<div>In scenarios where a large amount of data needs to be learned, incremental learning can make full use of old knowledge, significantly reduce the computational cost of the overall learning process, and maintain high performance. In this paper, taking the MaxCut problem as our example, we introduce the idea of incremental learning into quantum computing, and propose a Quantum Proactive Incremental Learning algorithm (QPIL). Instead of a one-off training of quantum circuit, QPIL contains a multi-phase training on gradually-increased subgraphs of all vertices, proactively reducing large-scale problems to smaller ones to solve in steps, providing an efficient solution for MaxCut. Specifically, some vertices and corresponding edges are randomly selected for training to obtain optimized parameters of the quantum circuit at first. Then, in each incremental phase, the remaining vertices and corresponding edges are gradually added and the parameters obtained from the previous phase are reused in the parameter initialization of the current phase. We perform experiments on 120 different small-scale graphs, and it shows that QPIL performs superior to prevalent quantum and classical baselines in terms of approximation ratio (AR), time cost, anti-forgetting, and solving stability. In particular, QPIL’s AR surpasses 20% of mainstream quantum baselines, and the time cost is less than 1/5 of them. The idea of QPIL is expected to inspire efficient and high-quality solutions in large-scale MaxCut and other combinatorial optimization problems.</div>","PeriodicalId":774,"journal":{"name":"Science China Physics, Mechanics & Astronomy","volume":"68 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11433-024-2501-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142518362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Buffer-atom-mediated quantum logic gates with off-resonant modulated driving 缓冲原子介导的非共振调制驱动量子逻辑门

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-10-22 DOI: 10.1007/s11433-024-2478-8

Yuan Sun

{"title":"Buffer-atom-mediated quantum logic gates with off-resonant modulated driving","authors":"Yuan Sun","doi":"10.1007/s11433-024-2478-8","DOIUrl":"10.1007/s11433-024-2478-8","url":null,"abstract":"<div>Connectivity of two-qubit logic gates plays a crucial and indispensable role in quantum computation research. For the cold atom qubit platform, while the two-qubit Rydberg blockade gate has recently made rapid experimental progress, a pressing challenge is to improve connectivity in pursuit of genuine scalability without sacrificing speed or fidelity. A significant advancement in this direction can be achieved by introducing an extra buffer atom to extend the two-qubit gate beyond purely nearest-neighbor two-body interactions. The buffer atom couples with the two qubit atoms through nearest-neighbor interactions, even though the qubit atoms do not directly exert any physical influence on each other. The established method of off-resonant modulated driving (ORMD) is not only convenient but also lays the groundwork for this latest development. Although the atomic linkage structure here exhibits more complex interactions compared to previous two-body systems, the population can satisfactorily return to the ground state after the ground-Rydberg transition with a properly designed modulation waveform. This can be achieved through one-photon and two-photon ground-Rydberg transitions in common practices. Furthermore, with buffer atom relay or similar structures, it is possible to realize a two-qubit entangling gate between two distant qubit atoms. In addition to demonstrating that such solutions are feasible, the representative modulation patterns are analyzed, showcasing the versatility of buffer-atom-mediated two-qubit gates. From a broader perspective, these efforts enhance the resemblance between the cold atom qubit platform and the superconducting qubit system, with the buffer atom functioning like wires and junctions.</div>","PeriodicalId":774,"journal":{"name":"Science China Physics, Mechanics & Astronomy","volume":"67 12","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142518391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Final vitrification of monatomic metals 单原子金属的最终玻璃化

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-10-12 DOI: 10.1007/s11433-024-2482-4

Maozhi Li

引用次数: 0

Convergent Richtmyer-Meshkov instability on two-dimensional tri-mode interfaces 二维三模界面上的收敛里氏-梅什科夫不稳定性

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-09-27 DOI: 10.1007/s11433-024-2471-7

Zhigang Zhai, Jinru Xu, Xisheng Luo

{"title":"Convergent Richtmyer-Meshkov instability on two-dimensional tri-mode interfaces","authors":"Zhigang Zhai, Jinru Xu, Xisheng Luo","doi":"10.1007/s11433-024-2471-7","DOIUrl":"10.1007/s11433-024-2471-7","url":null,"abstract":"<div>Interfacial fluid mixing driven by a shock wave is a common phenomenon that occurs frequently in basic science research and in a variety of applications. In this work, shock-tube experiments on the developments of two-dimensional tri-mode interfaces accelerated by a convergent shock wave are performed. Eight sets of different combinations in the value of phase and that of amplitude in a tri-mode perturbed interface are studied to evaluate the effect of mode coupling on the amplitude growths of the basic modes. The qualitative results show that the phase combination obviously affects the interface morphologies and flow features. The alternation of each mode amplitude does not affect the major flow features, such as the number and arrangement of the bubbles and spikes, but affects the local interface features. Depending upon the phase combination, the mode amplitude growth is either promoted or suppressed by mode coupling relative to the single-mode counterpart. By considering the feedbacks from both the first-order and second-order mode couplings, the mode amplitude growth can be qualitatively predicted. Relative to dual-mode interface, mode coupling occurs earlier in tri-mode interface. For the sets of parameters we studied, the effect of initial phase on the amplitude growth is greater and occurs earlier for the mode with low mode number. In addition, the amplitude development of mode with high mode number is more affected by initial amplitudes of basic modes than that of mode with low mode number. The introduction of the third mode affects the amplitude growths of original two modes, but has little effect on the final mixing width growth. Finally, a theoretical model is proposed to predict the amplitude growth of each basic mode.</div>","PeriodicalId":774,"journal":{"name":"Science China Physics, Mechanics & Astronomy","volume":"67 12","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142414630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0