Physical Review A最新文献

{"title":"Bipartite representations and many-body entanglement of pure states of N indistinguishable particles","authors":"J. A. Cianciulli, R. Rossignoli, M. Di Tullio, N. Gigena, Federico Petrovich","doi":"10.1103/physreva.110.032414","DOIUrl":"https://doi.org/10.1103/physreva.110.032414","url":null,"abstract":"We analyze a general bipartite-like representation of arbitrary pure states of <i>N</i> indistinguishable partcles, valid for both bosons and fermions, based on <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>M</mi></math>- and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mo>(</mo><mi>N</mi><mo>−</mo><mi>M</mi><mo>)</mo></mrow></math>-particle states. It leads to exact <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mo>(</mo><mi>M</mi><mo>,</mo><mi>N</mi><mo>−</mo><mi>M</mi><mo>)</mo></mrow></math> Schmidt-like expansions of the state for any <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>M</mi><mo>&lt;</mo><mi>N</mi></mrow></math> and is directly related to the isospectral reduced <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>M</mi></math>- and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mo>(</mo><mi>N</mi><mo>−</mo><mi>M</mi><mo>)</mo></mrow></math>-body density matrices <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msup><mi>ρ</mi><mrow><mo>(</mo><mi>M</mi><mo>)</mo></mrow></msup></math> and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msup><mi>ρ</mi><mrow><mo>(</mo><mi>N</mi><mo>−</mo><mi>M</mi><mo>)</mo></mrow></msup></math>. The formalism also allows for reduced yet still exact Schmidt-like decompositions associated with blocks of these densities, in systems having a fixed fraction of the particles in some single-particle subspace. Monotonicity of the ensuing <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>M</mi></math>-body entanglement under a certain set of quantum operations is also discussed. Illustrative examples in fermionic and bosonic systems with pairing correlations are provided, which show that in the presence of dominant eigenvalues in <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msup><mi>ρ</mi><mrow><mo>(</mo><mi>M</mi><mo>)</mo></mrow></msup></math>, approximations based on a few terms of the pertinent Schmidt expansion can provide a reliable description of the state. The associated one- and two-body entanglement spectrum and entropies are also analyzed.","PeriodicalId":20146,"journal":{"name":"Physical Review A","volume":"6 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

{"title":"Ytterbium atom interferometry for dark matter searches","authors":"Yifan Zhou, Rowan Ranson, Michalis Panagiotou, Chris Overstreet","doi":"10.1103/physreva.110.033313","DOIUrl":"https://doi.org/10.1103/physreva.110.033313","url":null,"abstract":"We analyze the projected sensitivity of a laboratory-scale ytterbium atom interferometer to scalar, vector, and pseudoscalar dark matter signals. A frequency ratio measurement between two transitions in <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mmultiscripts><mi>Yb</mi><mprescripts></mprescripts><none></none><mn>171</mn></mmultiscripts></math> enables a search for variations of the fine-structure constant that could surpass existing limits by a factor of 100 in the mass range <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msup><mn>10</mn><mrow><mo>−</mo><mn>22</mn></mrow></msup></math>–<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msup><mn>10</mn><mrow><mo>−</mo><mn>16</mn></mrow></msup></math> eV. Differential accelerometry between ytterbium isotopes yields projected sensitivities to scalar and vector dark matter couplings that are stronger than the limits set by the MICROSCOPE equivalence principle test, and an analogous measurement in the MAGIS-100 long-baseline interferometer would be more sensitive than previous bounds by factors of 10 or more. A search for anomalous spin torque in MAGIS-100 is projected to reach similar sensitivity to atomic magnetometry experiments. We discuss strategies for mitigating the main systematic effects in each measurement. These results indicate that improved dark matter searches with ytterbium atom interferometry are technically feasible.","PeriodicalId":20146,"journal":{"name":"Physical Review A","volume":"99 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

{"title":"Future-input-dependent model for Greenberger-Horne-Zeilinger correlations","authors":"Izhar Neder, Nathan Argaman","doi":"10.1103/physreva.110.032209","DOIUrl":"https://doi.org/10.1103/physreva.110.032209","url":null,"abstract":"It is widely appreciated, due to Bell's theorem, that quantum phenomena are inconsistent with local-realist models. In this context, locality refers to local causality, and there is thus an open possibility for reproducing the quantum predictions with models which internally violate the causal arrow of time, while otherwise adhering to the relevant locality condition. So far, this possibility has been demonstrated only at a toy-model level, and only for systems involving one or two spins (or photons). The present work extends one of these models to quantum correlations between three or more spins which are entangled in the Greenberger-Horne-Zeilinger state.","PeriodicalId":20146,"journal":{"name":"Physical Review A","volume":"45 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

{"title":"Quantum sensing of ultralow temperature in biwire ultracold polar molecules","authors":"Abdelâali Boudjemâa, Karima Abbas, Asma Tahar Taiba, Qing-Shou Tan","doi":"10.1103/physreva.110.032611","DOIUrl":"https://doi.org/10.1103/physreva.110.032611","url":null,"abstract":"We present a systematic study of quantum sensing of ultralow temperature in biwire ultracold polar molecules of a quasi-one-dimensional (1D) trap by exploring the dynamics of two physically different qubit models. The two models consist of a trapped impurity atom that act as a temperature quantum sensor interacting with polar molecules reservoir, where dipole moments are aligned head-to-tail across the wires. Our model takes advantage of the adjustable interwire distance to accurately control the precision ultralow temperatures measurement. We show that the system undergoes a transition from Markovian to non-Markovian dynamics, which can be controlled by changing the interwire separation, the dipole-–dipole interaction (DDI), and the temperature. We characterize the thermometric performance using the quantum signal-to-noise ratio for both models and demonstrate that such a quantity exhibits a higher peak at ultralow temperature. We therefore emphasize that ultracold polar molecules are crucial for revolutionizing temperature sensing.","PeriodicalId":20146,"journal":{"name":"Physical Review A","volume":"1 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

{"title":"Robust estimation of nonlinear properties of quantum processes","authors":"Yuqing Wang, Guoding Liu, Zhenhuan Liu, Yifan Tang, Xiongfeng Ma, Hao Dai","doi":"10.1103/physreva.110.032415","DOIUrl":"https://doi.org/10.1103/physreva.110.032415","url":null,"abstract":"The accurate and robust estimation of quantum process properties is crucial for quantum information processing and many-body physics. Combining classical shadow tomography and randomized benchmarking, Helsen <i>et al.</i> introduced a method to estimate the linear properties of quantum processes. In this work, we focus on the estimation protocols of nonlinear process properties that are robust to state preparation and measurement errors. We introduce two protocols, both utilizing random gate sequences but employing different postprocessing methods, which make them suitable for measuring different nonlinear properties. The first protocol offers a robust and sound method to estimate the out-of-time-ordered correlation, as demonstrated numerically in an Ising model. The second protocol estimates unitarity, effectively characterizing the incoherence of quantum channels. We expect the two protocols to be useful tools for exploring quantum many-body physics and characterizing quantum processes.","PeriodicalId":20146,"journal":{"name":"Physical Review A","volume":"147 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

{"title":"Unified treatment of atomic excitation and ionization","authors":"N. W. Antonio, I. Bray, A. S. Kadyrov","doi":"10.1103/physreva.110.032810","DOIUrl":"https://doi.org/10.1103/physreva.110.032810","url":null,"abstract":"A unified treatment of atomic excitation and ionization in ion-atom collisions is proposed. It is demonstrated that the state-resolved excitation cross sections multiplied by <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msup><mi>n</mi><mn>3</mn></msup></math>, where <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>n</mi></math> is the principal quantum number of the excited state, and the corresponding partial singly differential ionization cross section form two parts of a single continuous function. This allows one to obtain the excitation cross section for any state including high-lying Rydberg states and the energy-differential ionization cross section at, and arbitrarily close to, the threshold. The proposed method can be used in any theoretical approaches to excitation and ionization and experimental measurements.","PeriodicalId":20146,"journal":{"name":"Physical Review A","volume":"28 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

{"title":"Error mitigation, optimization, and extrapolation on a trapped-ion testbed","authors":"Oliver G. Maupin, Ashlyn D. Burch, Brandon Ruzic, Christopher G. Yale, Antonio Russo, Daniel S. Lobser, Melissa C. Revelle, Matthew N. Chow, Susan M. Clark, Andrew J. Landahl, Peter J. Love","doi":"10.1103/physreva.110.032416","DOIUrl":"https://doi.org/10.1103/physreva.110.032416","url":null,"abstract":"Current noisy intermediate-scale quantum (NISQ) trapped-ion devices are subject to errors which can significantly impact the accuracy of calculations if left unchecked. A form of error mitigation called zero noise extrapolation (ZNE) can decrease an algorithm's sensitivity to these errors without increasing the number of required qubits. Here we explore different methods for integrating this error mitigation technique into the Variational Quantum Eigensolver (VQE) algorithm for calculating the ground state of the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msup><mtext>HeH</mtext><mo>+</mo></msup></math> molecule at <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>0.8</mn><mspace width=\"3.33333pt\"></mspace><mtext>Å</mtext></mrow></math> in the presence of experimental noise. Using the Quantum Scientific Computing Open User Testbed (QSCOUT) trapped-ion device, we test three methods of scaling noise for extrapolation: time stretching the two-qubit gates, scaling the sideband detuning parameter, and inserting two-qubit gate identity operations into the ansatz circuit. We find that time stretching and sideband detuning scaling fail to scale the noise on our particular hardware in a way that can be extrapolated to zero noise. Scaling our noise with global gate identity insertions and extrapolating after variational optimization, we achieve error suppression of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>96.8</mn><mo>%</mo></mrow></math>, resulting in an energy estimate within <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mo>−</mo><mn>0.004</mn><mo>±</mo><mn>0.04</mn></mrow></math> hartree of the ground state energy. This is an improvement, but still outside the chemical accuracy threshold of 0.0016 hartree. Our results show that the efficacy of this error mitigation technique depends on choosing the correct implementation for a given device architecture.","PeriodicalId":20146,"journal":{"name":"Physical Review A","volume":"65 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

{"title":"Quantum thermodynamics of the spin-boson model using the principle of minimal dissipation","authors":"Salvatore Gatto, Alessandra Colla, Heinz-Peter Breuer, Michael Thoss","doi":"10.1103/physreva.110.032210","DOIUrl":"https://doi.org/10.1103/physreva.110.032210","url":null,"abstract":"A recently developed approach to the thermodynamics of open quantum systems, on the basis of the principle of minimal dissipation, is applied to the spin-boson model. Employing a numerically exact quantum dynamical treatment based on the hierarchical equations of motion (HEOM) method, we investigate the influence of the environment on quantities such as work, heat, and entropy production in a range of parameters which go beyond the weak-coupling limit and include both the nonadiabatic and the adiabatic regimes. The results reveal significant differences to the weak-coupling forms of work, heat, and entropy production, which are analyzed in some detail.","PeriodicalId":20146,"journal":{"name":"Physical Review A","volume":"27 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

{"title":"Implementation of controlled-not quantum gate by nonlinear coupled electro-nano-optomechanical oscillators","authors":"Reihaneh Alinaghipour, Hamidreza Mohammadi","doi":"10.1103/physreva.110.032412","DOIUrl":"https://doi.org/10.1103/physreva.110.032412","url":null,"abstract":"A feasibility study is done for the possibility of a universal set of quantum gate implementation based on phononic state via fourth-order Duffing nonlinearity in an optomechanical system. The optomechanical system consists of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>N</mi></mrow></math> doubly clamped coupled nanobeam arrays driven by local static and radio frequency electrical potentials, coupled to a single-mode high-finesse optical cavity. The results show that the ideal <span>cnot</span> gate can be implemented only under nonresonance dynamics when the dissipation processes are negligible.","PeriodicalId":20146,"journal":{"name":"Physical Review A","volume":"65 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

{"title":"Isotope-shift measurement of the 423-nm transition in neutral Ca","authors":"David Röser, Lukas Möller, Hans Keßler, Simon Stellmer","doi":"10.1103/physreva.110.032809","DOIUrl":"https://doi.org/10.1103/physreva.110.032809","url":null,"abstract":"We report on saturated absorption spectroscopy measurements of the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mrow><mo>(</mo><mn>4</mn><msup><mi>s</mi><mn>2</mn></msup><mo>)</mo></mrow><mmultiscripts><mi>S</mi><mn>0</mn><none></none><mprescripts></mprescripts><none></none><mn>1</mn></mmultiscripts><mo>→</mo><mrow><mo>(</mo><mn>4</mn><mi>s</mi><mn>4</mn><mi>p</mi><mo>)</mo></mrow><mmultiscripts><mi>P</mi><mn>1</mn><none></none><mprescripts></mprescripts><none></none><mn>1</mn></mmultiscripts></mrow></math> transition for the four most abundant even-mass isotopes in calcium. By referencing the laser locked to an ultralow expansion cavity and carefully investigating systematic errors, isotope shifts are determined with a precision below <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>100</mn><mspace width=\"0.16em\"></mspace><mi mathvariant=\"normal\">k</mi><mi>Hz</mi></mrow></math>, improving previously reported values by a factor of about 3. A King plot analysis, employing literature values of the 729-<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mspace width=\"0.16em\"></mspace><mi mathvariant=\"normal\">n</mi><mi mathvariant=\"normal\">m</mi></mrow></math> transition in <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msup><mi>Ca</mi><mo>+</mo></msup></math> ions, shows excellent linearity. The field and mass shift parameters are determined from King plots with other transitions.","PeriodicalId":20146,"journal":{"name":"Physical Review A","volume":"7 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}