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Inter-species spin-noise correlations in hot atomic vapors

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arXiv 2023年

作者： Mouloudakis, K. Vouzinas, F. Margaritakis, A. Koutsimpela, A. Mouloudakis, G. Koutrouli, V. Skotiniotis, M. Tsironis, G.P. Loulakis, M. Mitchell, M.W. Vasilakis, G. Kominis, I.K. Department of Physics University of Crete Heraklion71003 Greece ICFO - Institut de Ciències Fotòniques The Barcelona Institute of Science and Technology Castelldefels Barcelona08860 Spain School of Applied Mathematical and Physical Sciences National Technical University of Athens Athens15780 Greece Institute of Electronic Structure and Laser Foundation for Research and Technology Heraklion71110 Greece Física Teòrica: Informació i Fenòmens Quàntics Departament de Física Universitat Autònoma de Barcelona Bellaterra08193 Spain Departamento de Electromagnetismo y Física de la Materia Universidad de Granada Granada18010 Spain Institute of Theoretical and Computational Physics University of Crete Heraklion70013 Greece Institute of Applied and Computational Mathematics Foundation for Research and Technology Heraklion70013 Greece ICREA - Institució Catalana de Recerca i Estudis Avançats Barcelona08010 Spain Quantum Biometronics Heraklion71409 Greece

We report an experimental and theoretical study of spin noise correlations in a 87Rb-133Cs unpolarized alkali-metal vapor dominated by spin-exchange collisions. We observe strong unequal-time inter-species correlations and account for these with a first-principles theoretical model. Since the two atomic species have different spin precession frequencies, the dual-species vapor enables the use of an additional experimental handle, the applied magnetic field, for untangling various subtypes of spin correlations. In particular, the measured cross-correlation and auto-correlation spectra shed light on a number of spin-dynamic effects involving intra-atom, inter-atom, intra-species and inter-species correlations. Cross-correlation coefficients exceeding 60% have been observed at low-magnetic fields, where the two spin species couple strongly via spin-exchange collisions. The understanding of such spontaneously generated correlations can motivate the design of quantum-enhanced measurements with single or multi-species spin-polarized alkali-metal vapors used in quantum sensing applications. © 2023, CC BY.

关键词： Atoms

Image Recovery from Rotational And Translational Invariants

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Image Recovery from Rotational And Translational Invariants

IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Nicholas F. Marshall Ti-Yen Lan Tamir Bendory Amit Singer Department of Mathematics Princeton University Princeton NJ USA The Program in Applied and Computational Mathematics Princeton University Princeton NJ USA School of Electrical Engineering Tel Aviv University Tel Aviv Israel

ISBN: (数字)9781509066315

ISBN: (纸本)9781509066322

We introduce a framework for recovering an image from its rotationally and translationally invariant features based on autocorrelation analysis. This work is an instance of the multi-target detection statistical model, which is mainly used to study the mathematical and computational properties of single-particle reconstruction using cryo-electron microscopy (cryo-EM) at low signal-to-noise ratios. We demonstrate with synthetic numerical experiments that an image can be reconstructed from rotational and translational invariants and show that the reconstruction is robust to noise. These results constitute an important step towards the goal of structure determination of small biomolecules using cryo-EM.

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Polysulfide-Mediated Solvation Shell Reorganization for Fast Li+ Transfer Probed by In-Situ Sum Frequency Generation Spectroscopy

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SSRN

SSRN 2023年

作者： Wang, Jian Liu, Haitao Zhang, Jing Xiao, Qingbo Wang, Chong Zhang, Yongzheng Liu, Meinan Kang, Qi Jia, Lujie Wang, Dong Li, Qi Duan, Wenhui Adenusi, Henry Passerini, Stefano Zhang, Yuegang Lin, Hongzhen i-Lab & CAS Key Laboratory of Nanophotonic Materials and Devices Suzhou Institute of Nano-tech and Nano-bionics Chinese Academy of Sciences Suzhou215123 China UlmD89081 Germany KarlsruheD-76021 Germany Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Beijing100088 China School of Materials Science and Engineering Xi’an University of Technology Xi’an710048 China Department of Physics Tsinghua University Beijing100084 China State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai200237 China Department of Polymer Science and Engineering Shanghai Jiao Tong University Shanghai200240 China Key Laboratory of Automobile Materials of MOE School of Materials Science and Engineering Jilin University Changchun130012 China The University of Hong Kong Department of Chemistry Pokfulam Road Hong Kong Hong Kong Quantum AI Lab 17 Science Park West Avenue Hong Kong Sapienza University of Rome Chemistry Department P. A. Moro 5 Rome00185 Italy

Understanding of interfacial Li+ solvation shell structures and dynamic evolution at the electrode/electrolyte interface is requisite for developing high-energy-density Li batteries. Herein, the reorganization of Li+ solvation shell at the sulfur/electrolyte interface along with the presence of a trace amount of lithium polysulfides is verified by in-situ sum frequency generation (SFG) spectroscopy together with density functional theory (DFT) calculations. Both the spectroelectrochemical and DFT calculation results reveal a strongly competitive anion adsorption of the polysulfide anion additive against the pristine electrolyte anions on the sulfur cathode surface, reorganizing the interfacial local solvation shell structure facilitating rapid Li ion transfer and conduction. Meanwhile, the evolution of the SFG signals along with the discharging/charging cycle exhibits improved reversibility, indicating the transformation of the inner Helmholtz plane layer into a stable molecular-layer polysulfide interphase rather than a dynamic diffusion layer. Consequently, applications in practical Li-S batteries reveal the capacity and cycling stability of the corresponding cells are significantly enhanced. Our work provides a methodology using in-situ SFG for probing solvation reorganization of charge carriers at electrochemical interfaces. © 2023, The Authors. All rights reserved.

关键词： Negative ions

Using dynamic mode decomposition to predict the dynamics of a two-time non-equilibrium Green's function

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arXiv 2022年

作者： Yin, Jia Chan, Yang-Hao da Jornada, Felipe Qiu, Diana Louie, Steven G. Yang, Chao Applied Mathematics & Computational Research Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Institute of Atomic and Molecular Sciences Academia Sinica Taipei10617 Taiwan Department of Materials Science and Engineering Stanford University StanfordCA94305 United States School of Engineering & Applied Science Yale University New HavenCT06520 United States Department of Physics University of California at Berkeley BerkeleyCA94720 United States Materials Sciences Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States

Computing the numerical solution of the Kadanoff-Baym equations, a set of nonlinear integral differential equations satisfied by two-time Green's functions derived from many-body perturbation theory for a quantum many-body system away from equilibrium, is a challenging task. Recently, we have successfully applied dynamic mode decomposition (DMD) to construct a data driven reduced order model that can be used to extrapolate the time-diagonal of a two-time Green's function from numerical solution of the KBE within a small time window. In this paper, we extend the previous work and use DMD to predict off-diagonal elements of the two-time Green's function. We partition the two-time Green's function into a number of one-time functions along the diagonal and subdiagonls of the two-time window as well as in horizontal and vertical directions. We use DMD to construct separate reduced order models to predict the dynamics of these one-time functions in a two-step procedure. We extrapolate along diagonal and several subdiagonals within a subdiagonal band of a two-time window in the first step. In the second step, we use DMD to extrapolate the Green's function outside of the sub-diagonal band. We demonstrate the efficiency and accuracy of this approach by applying it to a two-band Hubbard model *** Codes 81Q40, 82C10 Copyright © 2022, The Authors. All rights reserved.

关键词： Extrapolation

Threshold and decay properties of transient isolated turbulent band in plane Couette flow

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applied mathematics and Mechanics(English Edition) 2019年第10期40卷 1449-1456页

作者： Jianzhou LU Jianjun TAO Weitao ZHOU Xiangming XIONG CAPT-HEDPS SKLTCS Collaborative Innovation Center of IFSA Department of Mechanics and Engineering Science College of Engineering Peking University Beijing 100871 China The Program in Applied and Computational Mathematics Princeton University Princeton NJ 08544 U. S.A.

By direct numerical simulations of the plane Couette flow (PCF) in a large computational domain, it is shown that an isolated turbulent band decays monotonically at low Reynolds numbers but experiences transient growth before the eventual relaminarization at moderate Reynolds numbers. The lower bound Reynolds number of the transient-growth regime is determined as 286. The width, length, and tilt angle of the iso- lated band structure are defined based on the disturbance kinetic energy in the mid-plane, and the geometric characteristics of the band can be described with a tilted rectangle. It is illustrated that before its eventual fragmentation, the isolated turbulent band decays in a style of longitudinal contraction, where the center, width, and tilt angle of the band keep almost constant but the band length contracts with a statistically constant velocity.

关键词： plane Couette flow (PCF) subcritical transition turbulent band

Simulating Cardiac Fluid Dynamics in the Human Heart

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arXiv 2023年

作者： Davey, Marshall Puelz, Charles Rossi, Simone Smith, Margaret Anne Wells, David R. Sturgeon, Gregory M. Segars, W. Paul Vavalle, John P. Peskin, Charles S. Griffith, Boyce E. University of North Carolina Chapel HillNC United States Department of Pediatrics-Cardiology Baylor College of Medicine Texas Children’s Hospital HoustonTX United States Department of Mathematics University North Carolina Chapel HillNC United States Department of Radiology Duke University Medical Center DurhamNC United States Division of Cardiology Department of Medicine University of North Carolina School of Medicine Chapel HillNC United States Courant Institute of Mathematical Sciences New York University New YorkNY United States Departments of Mathematics and Biomedical Engineering University of North Carolina Chapel HillNC United States Carolina Center for Interdisciplinary Applied Mathematics University of North Carolina Chapel HillNC United States Computational Medicine Program University of North Carolina School of Medicine Chapel HillNC United States McAllister Heart Institute University of North Carolina School of Medicine Chapel HillNC United States

Cardiac fluid dynamics fundamentally involves interactions between complex blood flows and the structural deformations of the muscular heart walls and the thin, flexible valve leaflets. There has been longstanding scientific, engineering, and medical interest in creating mathematical models of the heart that capture, explain, and predict these fluid-structure interactions. However, existing computational models that account for interactions among the blood, the actively contracting myocardium, and the cardiac valves are limited in their abilities to predict valve performance, resolve fine-scale flow features, or use realistic descriptions of tissue biomechanics. Here we introduce and benchmark a comprehensive mathematical model of cardiac fluid dynamics in the human heart. A unique feature of our model is that it incorporates biomechanically detailed descriptions of all major cardiac structures that are calibrated using tensile tests of human tissue specimens to reflect the heart’s microstructure. Further, it is the first fluid-structure interaction model of the heart that provides anatomically and physiologically detailed representations of all four cardiac valves. We demonstrate that this integrative model generates physiologic dynamics, including realistic pressure-volume loops that automatically capture isovolumetric contraction and relaxation, and predicts fine-scale flow features. None of these outputs are prescribed;instead, they emerge from interactions within our comprehensive description of cardiac physiology. Such models can serve as tools for predicting the impacts of medical devices or clinical interventions. They also can serve as platforms for mechanistic studies of cardiac pathophysiology and dysfunction, including congenital defects, cardiomyopathies, and heart failure, that are difficult or impossible to perform in patients. Copyright © 2023, The Authors. All rights reserved.

关键词： Heart

Quantum Simulation for High-Energy physics

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PRX Quantum 2023年第2期4卷 027001-027001页

作者： Christian W. Bauer Zohreh Davoudi A. Baha Balantekin Tanmoy Bhattacharya Marcela Carena Wibe A. de Jong Patrick Draper Aida El-Khadra Nate Gemelke Masanori Hanada Dmitri Kharzeev Henry Lamm Ying-Ying Li Junyu Liu Mikhail Lukin Yannick Meurice Christopher Monroe Benjamin Nachman Guido Pagano John Preskill Enrico Rinaldi Alessandro Roggero David I. Santiago Martin J. Savage Irfan Siddiqi George Siopsis David Van Zanten Nathan Wiebe Yukari Yamauchi Kübra Yeter-Aydeniz Silvia Zorzetti Physics Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA Department of Physics Maryland Center for Fundamental Physics and the NSF Institute for Robust Quantum Simulation University of Maryland College Park Maryland 20742 USA Department of Physics University of Wisconsin Madison Wisconsin 53706 USA T-2 Los Alamos National Laboratory Los Alamos New Mexico 87545 USA Fermi National Accelerator Laboratory Batavia Illinois 60510 USA Enrico Fermi Institute University of Chicago Chicago Illinois 60637 USA Kavli Institute for Cosmological Physics University of Chicago Chicago Illinois 60637 USA Department of Physics University of Chicago Chicago Illinois 60637 USA Department of Physics and Illinois Center for the Advanced Study of the Universe and Illinois Quantum Information Science and Technology Center University of Illinois Urbana Illinois 61801 USA QuEra Computing Inc Boston Massachusetts 02135 USA Department of Mathematics University of Surrey Guildford Surrey GU2 7XH United Kingdom Center for Nuclear Theory Department of Physics and Astronomy Stony Brook University New York 11794-3800 USA Department of Physics Brookhaven National Laboratory Upton New York 11973 USA Peng Huanwu Center for Fundamental Theory Hefei Anhui 230026 China Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei Anhui 230026 China Pritzker School of Molecular Engineering Chicago Quantum Exchange and Kadanoff Center for Theoretical Physics University of Chicago Illinois 60637 USA qBraid Co. Harper Court 5235 Chicago Illinois 60615 USA Department of Physics Harvard University Cambridge Massachusetts 02138 USA Department of Physics and Astronomy University of Iowa Iowa City Iowa 52242 USA Duke Quantum Center Duke University Durham North Carolina 27701 USA Department of Electrical and Computer Engineering Duke University Durham North Carolina 27708 USA Department of Physics Duke University

It is for the first time that quantum simulation for high-energy physics (HEP) is studied in the U.S. decadal particle-physics community planning, and in fact until recently, this was not considered a mainstream topic in the community. This fact speaks of a remarkable rate of growth of this subfield over the past few years, stimulated by the impressive advancements in quantum information sciences (QIS) and associated technologies over the past decade, and the significant investment in this area by the government and private sectors in the U.S. and other countries. High-energy physicists have quickly identified problems of importance to our understanding of nature at the most fundamental level, from tiniest distances to cosmological extents, that are intractable with classical computers but may benefit from quantum advantage. They have initiated, and continue to carry out, a vigorous program in theory, algorithm, and hardware co-design for simulations of relevance to the HEP mission. This Roadmap is an attempt to bring this exciting and yet challenging area of research to the spotlight, and to elaborate on what the promises, requirements, challenges, and potential solutions are over the next decade and beyond.

关键词： Quantum simulation

Hyperfine structure of 173Yb+: toward resolving the 173Yb nuclear octupole moment puzzle

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arXiv 2020年

作者： Xiao, Di Li, Jiguang Campbell, Wesley C. Dellaert, Thomas McMillin, Patrick Ransford, Anthony Roman, Conrad Derevianko, Andrei Department of Physics University of Nevada Reno89557 United States Institute of Applied Physics and Computational Mathematics Beijing100088 China Department of Physics and Astronomy Center for Quantum Science and Engineering University of California Los Angeles United States

Hyperfine structure (HFS) of atomic energy levels arises due to interactions of atomic electrons with a hierarchy of nuclear multipole moments, including magnetic dipole, electric quadrupole and higher rank moments. Recently, a determination of the magnetic octupole moment of the 173Yb nucleus was reported from HFS measurements in neutral 173Yb [PRA 87, 012512 (2013)], and is four orders of magnitude larger than the nuclear theory prediction. Considering this substantial discrepancy between the spectroscopically extracted value and nuclear theory, here we propose to use an alternative system to resolve this tension, a singly charged ion of the same 173Yb isotope. Utilizing the substantial suite of tools developed around Yb+ for quantum information applications, we propose to extract nuclear octupole and hexadecapole moments from measuring hyperfine splittings in the extremely long lived first excited state (4f13(2Fo)6s2, J = 7/2) of 173Yb+. We present results of atomic structure calculations in support of the proposed measurements. Copyright © 2020, The Authors. All rights reserved.

关键词： Excited states

Explanation of the anomalous redshift on nonlinear X-ray Compton scattering spectrum by a bound electron

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arXiv 2021年

作者： Shi, Shang Chen, Jing Yang, Yujun Yan, Zhong-Chao Liu, Xiaojun Wang, Bingbing Laboratory of Optical Physics Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing100190 China HEDPS Center for Applied Physics and Technology Peking University Beijing100871 China Institute of Applied Physics and Computational Mathematics Beijing100088 China Insititute of Atomic and Molecular Physics Jilin University Changchun130012 China Department of Physics University of New Brunswick FrederictonNBE3B 5A3 Canada State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Innovation Academy for Precision Measurement Science and Technology Chinese Academy of Sciences Wuhan430071 China University of Chinese Academy of Sciences Beijing100049 China

Nonlinear Compton scattering is an inelastic scattering process where a photon is emitted due to the interaction between an electron and an intense laser field. With the development of X-ray free-electron lasers, the intensity of X-ray laser is greatly enhanced, and the signal from X-ray nonlinear Compton scattering is no longer weak. Although the nonlinear Compton scattering by an initially free electron has been thoroughly investigated, the mechanism of nonrelativistic nonlinear Compton scattering of X-ray photons by bound electrons is unclear yet. Here, we present a frequency-domain formulation based on the nonperturbative quantum electrodynamic to study nonlinear Compton scattering of two photons off a bound electron inside an atom in a strong X-ray laser field. In contrast to previous theoretical works, our results clearly reveal the existence of anomalous redshift phenomenon observed experimentally by Fuchs et al. (Nat. Phys. 11, 964 (2015)) and suggest its origin as the binding energy of the electron as well as the momentum transfer from incident photons to the electron during the scattering process. Our work builds a bridge between intense-laser atomic physics and Compton scattering process that can be used to study atomic structure and dynamics at high laser intensities. Copyright © 2021, The Authors. All rights reserved.

关键词： Atoms