Science China Physics, Mechanics & Astronomy最新文献_第8页

Improved Reall-Santos method for AdS black holes in general 4-derivative gravities 一般 4 衍生引力中 AdS 黑洞的改进 Reall-Santos 方法

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-07-19 DOI: 10.1007/s11433-024-2398-1

Peng-Ju Hu, Liang Ma, Hong Lü, Yi Pang

{"title":"Improved Reall-Santos method for AdS black holes in general 4-derivative gravities","authors":"Peng-Ju Hu, Liang Ma, Hong Lü, Yi Pang","doi":"10.1007/s11433-024-2398-1","DOIUrl":"10.1007/s11433-024-2398-1","url":null,"abstract":"<div>For asymptotically flat black holes, Reall-Santos method is a convenient tool to compute leading higher derivative corrections to the thermodynamic quantities without actually solving the modified field equations. However, there are subtleties in its generalization to asymptotically AdS black holes with general higher derivative corrections. First of all, it is necessary to know all the higher derivative holographic counterterms and the surface terms implementing the variational principle and subtracting the divergence. One then needs to solve for the modified AdS radius and rescale the time coordinate in an appropriate way such that the induced metric on the conformal boundary of AdS black hole is not modified. We observe that Reall-Santos method can be directly applied to a particular 4-derivative gravity model, known as the Einstein-Weyl gravity, which does not modify the AdS radius and requires only the Gibbons-Hawking-York term and holographic counterterms for the 2-derivative theory. We thus suggest that to compute the thermodynamic quantities of AdS black holes in general 4-derivative theories of gravity, one simply needs to transform it to a Einstein-Weyl gravity with identical thermodynamic variables by appropriate field redefinitions. We explicitly verify this proposal with spherically-symmetric and static charged black holes in Einstein-Maxwell theory extended with generic 4-derivative interactions.</div>","PeriodicalId":774,"journal":{"name":"Science China Physics, Mechanics & Astronomy","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141782857","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

Solving the subset sum problem by the quantum Ising model with variational quantum optimization based on conditional values at risk 用基于风险条件值的变分量子优化解决量子伊辛模型的子集和问题

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-07-18 DOI: 10.1007/s11433-024-2385-7

Qilin Zheng, Miaomiao Yu, Pingyu Zhu, Yan Wang, Weihong Luo, Ping Xu

{"title":"Solving the subset sum problem by the quantum Ising model with variational quantum optimization based on conditional values at risk","authors":"Qilin Zheng, Miaomiao Yu, Pingyu Zhu, Yan Wang, Weihong Luo, Ping Xu","doi":"10.1007/s11433-024-2385-7","DOIUrl":"10.1007/s11433-024-2385-7","url":null,"abstract":"<div>The subset sum problem is a combinatorial optimization problem, and its complexity belongs to the nondeterministic polynomial time complete (NP-Complete) class. This problem is widely used in encryption, planning or scheduling, and integer partitions. An accurate search algorithm with polynomial time complexity has not been found, which makes it challenging to be solved on classical computers. To effectively solve this problem, we translate it into the quantum Ising model and solve it with a variational quantum optimization method based on conditional values at risk. The proposed model needs only n qubits to encode 2n dimensional search space, which can effectively save the encoding quantum resources. The model inherits the advantages of variational quantum algorithms and can obtain good performance at shallow circuit depths while being robust to noise, and it is convenient to be deployed in the Noisy Intermediate Scale Quantum era. We investigate the effects of the scalability, the variational ansatz type, the variational depth, and noise on the model. Moreover, we also discuss the performance of the model under different conditional values at risk. Through computer simulation, the scale can reach more than nine qubits. By selecting the noise type, we construct simulators with different QVs and study the performance of the model with them. In addition, we deploy the model on a superconducting quantum computer of the Origin Quantum Technology Company and successfully solve the subset sum problem. This model provides a new perspective for solving the subset sum problem.</div>","PeriodicalId":774,"journal":{"name":"Science China Physics, Mechanics & Astronomy","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141782859","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

Spin asymmetry and dipole moments in τ-pair production with ultraperipheral heavy ion collisions 超外围重离子碰撞产生的τ对中的自旋不对称和偶极矩

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-07-18 DOI: 10.1007/s11433-024-2389-y

Dingyu Shao, Bin Yan, Shu-Run Yuan, Cheng Zhang

引用次数: 0

Signifying quantum uncertainty relations by optimal observable sets and the tightest uncertainty constants 用最优观测集和最严格不确定性常数表示量子不确定性关系

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-07-18 DOI: 10.1007/s11433-024-2409-7

Xiao-Bin Liang, Bo Li, Shao-Ming Fei

引用次数: 0

Supertetragonal BaZrS3: A promising perovskite sulphide with giant ferroelectricity and low band gap 超四方 BaZrS3：具有巨铁电性和低带隙的前景广阔的过氧化物硫化物

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-07-18 DOI: 10.1007/s11433-024-2394-1

Menglu Li, Sa Zhang, Chenhan Liu, Xiaotao Zu, Liang Qiao, Haiyan Xiao

{"title":"Supertetragonal BaZrS3: A promising perovskite sulphide with giant ferroelectricity and low band gap","authors":"Menglu Li, Sa Zhang, Chenhan Liu, Xiaotao Zu, Liang Qiao, Haiyan Xiao","doi":"10.1007/s11433-024-2394-1","DOIUrl":"10.1007/s11433-024-2394-1","url":null,"abstract":"<div>Over the past century, ferroelectricity has offered exciting opportunities for fundamental research and device applications. However, most of the discovered excellent ferroelectrics are oxide materials with large band gaps, limiting their potential for optoelectronics applications. Here using first-principles calculations we identify a new narrow-gap ferroelectric beyond oxides, i.e., ferroelectric perovskite sulphide BaZrS3. Under large compressive strains, BaZrS3 can be stabilized into a unique super-tetragonal phase with an extraordinary polarization of 67.16 µC/cm2, which is even stronger than that of conventional oxide ferroelectrics. Excitingly, the supertetragonal BaZrS3 exhibits a direct narrow band gap of 1.2 eV and excellent electronic properties. Based on the chemical bonding analysis, we attribute the formation of supertetragonal phase to charge re-ordering in which the π bond overlap along the long 〈Zr-S〉 bond completely vanishes and the antibonding states of the σ bond appear below the Fermi level. Our work provides a conceptual strategy for designing new ferroelectrics for electronic and photovoltaic applications.</div>","PeriodicalId":774,"journal":{"name":"Science China Physics, Mechanics & Astronomy","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141782904","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

Sodium metals for single emitter strong coupling: Alternative plasmonic candidates beyond noble metals 用于单发射极强耦合的钠金属：贵金属之外的另一种等离子候选材料

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-07-17 DOI: 10.1007/s11433-024-2407-6

Yi Zhang, Shuying Chen, Yuning Han, Xiulai Xu, Lin Zhou

引用次数: 0

Improving constraint on Ωm from SDSS using marked correlation functions 利用标记相关函数改进 SDSS 对 Ωm 的约束

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-07-17 DOI: 10.1007/s11433-023-2384-4

Limin Lai, Jiacheng Ding, Xiaolin Luo, Yizhao Yang, Zihan Wang, Keshi Liu, Guanfu Liu, Xin Wang, Yi Zheng, Zhaoyu Li, Le Zhang, Xiao-Dong Li

{"title":"Improving constraint on Ωm from SDSS using marked correlation functions","authors":"Limin Lai, Jiacheng Ding, Xiaolin Luo, Yizhao Yang, Zihan Wang, Keshi Liu, Guanfu Liu, Xin Wang, Yi Zheng, Zhaoyu Li, Le Zhang, Xiao-Dong Li","doi":"10.1007/s11433-023-2384-4","DOIUrl":"10.1007/s11433-023-2384-4","url":null,"abstract":"<div>Large-scale structure (LSS) surveys will increasingly provide stringent constraints on our cosmological models. Recently, the density-marked correlation function (MCF) has been introduced, offering an easily computable density-correlation statistic. Simulations have demonstrated that MCFs offer additional, independent constraints on cosmological models beyond the standard two-point correlation (2PCF). In this study, we apply MCFs for the first time to SDSS CMASS data, aiming to investigate the statistical information regarding clustering and anisotropy properties in the Universe and assess the performance of various weighting schemes in MCFs, and finally obtain constraints on Ωm. Upon analyzing the CMASS data, we observe that, by combining different weights (α = [−0.2, 0, 0.2, 0.6]), the MCFs provide a tight and independent constraint on the cosmological parameter Ωm, yielding Ωm = 0.293 ± 0.006 at the 1σ level, which represents a significant reduction in the statistical error by a factor of 3.4 compared to that from 2PCF. Our constraint is consistent with recent findings from the small-scale clustering of BOSS galaxies (Zhai et al. Astronphys. J. 948, 99 (2023)) within the 1σ level. However, we also find that our estimate is lower than the Planck measurements by about 2.6σ, indicating the potential presence of new physics beyond the standard cosmological model if all the systematics are fully corrected. The method outlined in this study can be extended to other surveys and datasets, allowing for the constraint of other cosmological parameters. Additionally, it serves as a valuable tool for forthcoming emulator analysis on the Chinese Space Station Telescope (CSST).</div>","PeriodicalId":774,"journal":{"name":"Science China Physics, Mechanics & Astronomy","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141782907","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 fluxes on generic orbits in near-extreme Kerr spacetime: Higher spin and large eccentricity 近极端克尔时空中一般轨道上的引力波通量：高自旋和大偏心率

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-07-16 DOI: 10.1007/s11433-024-2431-0

Changkai Chen, Jiliang Jing

引用次数: 0

Spectral observation of symmetry-protected selection rules for dynamical high-dimensional parity in alignment magnetic resonance 对准磁共振动态高维奇偶性对称保护选择规则的光谱观测

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-07-16 DOI: 10.1007/s11433-024-2428-y

Xu-Xing Geng, Kai Jin, Lu Zhou, Wang-Wang Tang, Guoqing Yang, Shangqing Liang, Shao-Ping Wu, Guang-Ming Huang, Gao-Xiang Li

{"title":"Spectral observation of symmetry-protected selection rules for dynamical high-dimensional parity in alignment magnetic resonance","authors":"Xu-Xing Geng, Kai Jin, Lu Zhou, Wang-Wang Tang, Guoqing Yang, Shangqing Liang, Shao-Ping Wu, Guang-Ming Huang, Gao-Xiang Li","doi":"10.1007/s11433-024-2428-y","DOIUrl":"10.1007/s11433-024-2428-y","url":null,"abstract":"<div>Multidimensional Floquet-driven alignment systems with dynamical symmetry present various exotic phenomena and applications. However, there are challenges in directly characterizing large-spin dynamical symmetry from spectra. Here, we first observe the symmetry-protected selection rules of dynamical high-dimensional parity in a large-spin (F = 4) system. We theoretically construct a Floquet-driven alignment system that can be used to reveal high-dimensional spatiotemporal symmetry. In the experiment, the system is implemented in Cs atomic gas subjected to two-dimensional Floquet-modulated magnetic resonance driving. By developing Floquet detection protocols of alignment double-sided spectra, we directly verify symmetry-protected selection rules of dynamical high-dimensional parity for large-spin systems. This work advances the exploration of dynamical symmetry to large spins, and unravels a universal Floquet scheme for the investigation of symmetry-protected selection rules.</div>","PeriodicalId":774,"journal":{"name":"Science China Physics, Mechanics & Astronomy","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141741681","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

Fermi level tuning in Sn1-xPbxTe/Pb heterostructure via changing interface roughness 通过改变界面粗糙度调谐 Sn1-xPbxTe/Pb 异质结构中的费米级

IF 6.4 1区物理与天体物理

Science China Physics, Mechanics & Astronomy Pub Date : 2024-07-16 DOI: 10.1007/s11433-024-2383-6

Tengteng Liu, Zhaoxia Yi, Bangjin Xie, Weiyan Zheng, Dandan Guan, Shiyong Wang, Hao Zheng, Canhua Liu, Hao Yang, Yaoyi Li, Jinfeng Jia

{"title":"Fermi level tuning in Sn1-xPbxTe/Pb heterostructure via changing interface roughness","authors":"Tengteng Liu, Zhaoxia Yi, Bangjin Xie, Weiyan Zheng, Dandan Guan, Shiyong Wang, Hao Zheng, Canhua Liu, Hao Yang, Yaoyi Li, Jinfeng Jia","doi":"10.1007/s11433-024-2383-6","DOIUrl":"10.1007/s11433-024-2383-6","url":null,"abstract":"<div>Superconducting SnTe-type topological crystalline insulators (TCIs) are predicted to host multiple Majorana zero modes (MZMs) which can coexist in a single vortex. Fermi level (FL) close to the Dirac points of topological surface states is helpful for detecting MZMs. However, the TCI SnTe is a heavily p-type semiconductor which is very difficult to modify to n-type via doping or alloying. In this work, we fabricate the atomically flat Sn1-xPbxTe/Pb heterostructure by molecular beam epitaxy, and make the p-type Sn1-xPbxTe become n-type through changing the interface roughness. Using scanning tunnelling microscope, we find the Dirac points of Sn1-xPbxTe/Pb heterostructure are always above the FL due to the Fermi level pinning (FLP) induced by topological surface states at atomically flat interface. After increasing the interface roughness, the FLP effect is suppressed and then the Dirac points of p-type Sn1-xPbxTe can be tuned very close to or even below the FL. Our work provides a new method for tuning the FL of SnTe-type TCI which has potential application in novel topological superconductor device.</div>","PeriodicalId":774,"journal":{"name":"Science China Physics, Mechanics & Astronomy","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141741683","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