PRL: General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

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Recently published articles in Phys. Rev. Lett. in the Table of Content section "General Physics: Statistical and Quantum Mechanics, Quantum Information, etc."
Updated: 18 hours 59 min ago

Conservation of Quantum Correlations in Multimode Systems with $U(1)$ Symmetry

Thu, 2018-07-12 12:00

Author(s): G. Buonaiuto, D. M. Whittaker, and E. Cancellieri

We present a theoretical investigation of the properties of quantum correlation functions in a multimode system. We define a total mth order equal-time correlation function, summed over all modes, which is shown to be conserved if the Hamiltonian possesses U(1) symmetry. It is also conserved in the ...

[Phys. Rev. Lett. 121, 020404] Published Thu Jul 12, 2018

Categories: Journals, Physics

Nonequilibrium Statistical Mechanics of Two-Dimensional Vortices

Thu, 2018-07-12 12:00

Author(s): Renato Pakter and Yan Levin

It has been observed empirically that two-dimensional vortices tend to cluster, forming a giant vortex. To account for this observation, Onsager introduced the concept of negative absolute temperature in equilibrium statistical mechanics. In this Letter, we show that in the thermodynamic limit a sys...

[Phys. Rev. Lett. 121, 020602] Published Thu Jul 12, 2018

Categories: Journals, Physics

Quantum Critical Metrology

Wed, 2018-07-11 12:00

Author(s): Irénée Frérot and Tommaso Roscilde

Quantum metrology fundamentally relies upon the efficient management of quantum uncertainties. We show that under equilibrium conditions the management of quantum noise becomes extremely flexible around the quantum critical point of a quantum many-body system: this is due to the critical divergence ...

[Phys. Rev. Lett. 121, 020402] Published Wed Jul 11, 2018

Categories: Journals, Physics

Giant Magnetoresistance in Hubbard Chains

Wed, 2018-07-11 12:00

Author(s): Jian Li, Chen Cheng, Thereza Paiva, Hai-Qing Lin, and Rubem Mondaini

We use numerically unbiased methods to show that the one-dimensional Hubbard model with periodically distributed on-site interactions already contains the minimal ingredients to display the phenomenon of magnetoresistance; i.e., by applying an external magnetic field, a dramatic enhancement on the c...

[Phys. Rev. Lett. 121, 020403] Published Wed Jul 11, 2018

Categories: Journals, Physics

Strong Coupling in Conserved Surface Roughening: A New Universality Class?

Wed, 2018-07-11 12:00

Author(s): Fernando Caballero, Cesare Nardini, Frédéric van Wijland, and Michael E. Cates

The Kardar-Parisi-Zhang (KPZ) equation defines the main universality class for nonlinear growth and roughening of surfaces. But under certain conditions, a conserved KPZ equation (CKPZ) is thought to set the universality class instead. This has non-mean-field behavior only in spatial dimension d<...

[Phys. Rev. Lett. 121, 020601] Published Wed Jul 11, 2018

Categories: Journals, Physics

Effective Theory of Nonadiabatic Quantum Evolution Based on the Quantum Geometric Tensor

Mon, 2018-07-09 12:00

Author(s): O. Bleu, G. Malpuech, Y. Gao, and D. D. Solnyshkov

We study the role of the quantum geometric tensor (QGT) in the evolution of two-band quantum systems. We show that all its components play an important role on the extra phase acquired by a spinor and on the trajectory of an accelerated wave packet in any realistic finite-duration experiment. While ...

[Phys. Rev. Lett. 121, 020401] Published Mon Jul 09, 2018

Categories: Journals, Physics

Quantum Limitation to the Coherent Emission of Accelerated Charges

Thu, 2018-07-05 12:00

Author(s): A. Angioi and A. Di Piazza

Accelerated charges emit electromagnetic radiation. According to classical electrodynamics, if the charges move along sufficiently close trajectories they emit coherently; i.e., their emitted energy scales quadratically with their number rather than linearly. By investigating the emission by a two-e...

[Phys. Rev. Lett. 121, 010402] Published Thu Jul 05, 2018

Categories: Journals, Physics

Quantum Algorithm for Spectral Measurement with a Lower Gate Count

Thu, 2018-07-05 12:00

Author(s): David Poulin, Alexei Kitaev, Damian S. Steiger, Matthew B. Hastings, and Matthias Troyer

We present two techniques that can greatly reduce the number of gates required to realize an energy measurement, with application to ground state preparation in quantum simulations. The first technique realizes that to prepare the ground state of some Hamiltonian, it is not necessary to implement th...

[Phys. Rev. Lett. 121, 010501] Published Thu Jul 05, 2018

Categories: Journals, Physics

One-Shot Coherence Distillation

Tue, 2018-07-03 12:00

Author(s): Bartosz Regula, Kun Fang, Xin Wang, and Gerardo Adesso

We characterize the distillation of quantum coherence in the one-shot setting, that is, the conversion of general quantum states into maximally coherent states under different classes of quantum operations. We show that the maximally incoherent operations (MIO) and the dephasing-covariant incoherent...

[Phys. Rev. Lett. 121, 010401] Published Tue Jul 03, 2018

Categories: Journals, Physics

Unfolding Hidden Barriers by Active Enhanced Sampling

Tue, 2018-07-03 12:00

Author(s): Jing Zhang and Ming Chen

Collective variable (CV) or order parameter based enhanced sampling algorithms have achieved great success due to their ability to efficiently explore the rough potential energy landscapes of complex systems. However, the degeneracy of microscopic configurations, originating from the orthogonal spac...

[Phys. Rev. Lett. 121, 010601] Published Tue Jul 03, 2018

Categories: Journals, Physics

Universal Quantum Magnetometry with Spin States at Equilibrium

Fri, 2018-06-29 12:00

Author(s): Filippo Troiani and Matteo G. A. Paris

We address metrological protocols for the estimation of the intensity and the orientation of a magnetic field, and show that quantum-enhanced precision may be achieved by probing the field with an arbitrary spin at thermal equilibrium. A general expression is derived for the ultimate achievable prec...

[Phys. Rev. Lett. 120, 260503] Published Fri Jun 29, 2018

Categories: Journals, Physics

Distinguishing Coherent and Thermal Photon Noise in a Circuit Quantum Electrodynamical System

Fri, 2018-06-29 12:00

Author(s): Fei Yan, Dan Campbell, Philip Krantz, Morten Kjaergaard, David Kim, Jonilyn L. Yoder, David Hover, Adam Sears, Andrew J. Kerman, Terry P. Orlando, Simon Gustavsson, and William D. Oliver

In the cavity-QED architecture, photon number fluctuations from residual cavity photons cause qubit dephasing due to the ac Stark effect. These unwanted photons originate from a variety of sources, such as thermal radiation, leftover measurement photons, and cross talk. Using a capacitively shunted ...

[Phys. Rev. Lett. 120, 260504] Published Fri Jun 29, 2018

Categories: Journals, Physics

Solvation in Space-time: Pretransition Effects in Trajectory Space

Fri, 2018-06-29 12:00

Author(s): Shachi Katira, Juan P. Garrahan, and Kranthi K. Mandadapu

We demonstrate pretransition effects in space-time in trajectories of systems in which the dynamics displays a first-order phase transition between distinct dynamical phases. These effects are analogous to those observed for thermodynamic first-order phase transitions, most notably the hydrophobic e...

[Phys. Rev. Lett. 120, 260602] Published Fri Jun 29, 2018

Categories: Journals, Physics

18-Qubit Entanglement with Six Photons’ Three Degrees of Freedom

Thu, 2018-06-28 12:00

Author(s): Xi-Lin Wang, Yi-Han Luo, He-Liang Huang, Ming-Cheng Chen, Zu-En Su, Chang Liu, Chao Chen, Wei Li, Yu-Qiang Fang, Xiao Jiang, Jun Zhang, Li Li, Nai-Le Liu, Chao-Yang Lu, and Jian-Wei Pan

An 18-qubit Greenberger-Horne-Zeilinger entangled state is created by using three degrees of freedom—path, polarization, and orbital angular momentum—of six photons.

[Phys. Rev. Lett. 120, 260502] Published Thu Jun 28, 2018

Categories: Journals, Physics

Efficient Quantum Measurement Engines

Wed, 2018-06-27 12:00

Author(s): Cyril Elouard and Andrew N. Jordan

We propose quantum engines powered entirely by a position-resolving measurement performed on a quantum particle. These engines produce work by moving the quantum particle against a force. Unlike classical information-driven engines (e.g., Maxwell’s demon), the energy is not extracted from a thermal ...

[Phys. Rev. Lett. 120, 260601] Published Wed Jun 27, 2018

Categories: Journals, Physics

Maximal Randomness Generation from Steering Inequality Violations Using Qudits

Tue, 2018-06-26 12:00

Author(s): Paul Skrzypczyk and Daniel Cavalcanti

We consider the generation of randomness based upon the observed violation of an Einstein-Podolsky-Rosen (EPR) steering inequality, known as one-sided device-independent randomness generation. We show that in the simplest scenario—involving only two parties and two measurements for the uncharacteris...

[Phys. Rev. Lett. 120, 260401] Published Tue Jun 26, 2018

Categories: Journals, Physics

Measuring the Winding Number in a Large-Scale Chiral Quantum Walk

Tue, 2018-06-26 12:00

Author(s): Xiao-Ye Xu, Qin-Qin Wang, Wei-Wei Pan, Kai Sun, Jin-Shi Xu, Geng Chen, Jian-Shun Tang, Ming Gong, Yong-Jian Han, Chuan-Feng Li, and Guang-Can Guo

We report the experimental measurement of the winding number in an unitary chiral quantum walk. Fundamentally, the spin-orbit coupling in discrete time quantum walks is implemented via a birefringent crystal collinearly cut based on a time-multiplexing scheme. Our protocol is compact and avoids extr...

[Phys. Rev. Lett. 120, 260501] Published Tue Jun 26, 2018

Categories: Journals, Physics

Work Storage in States of Apparent Negative Thermodynamic Temperature

Thu, 2018-06-21 12:00

Author(s): Henning Struchtrup

Inverted quantum states provide a challenge to classical thermodynamics, since they appear to contradict the classical formulation of the second law of thermodynamics. Ramsey interpreted these states as stable equilibrium states of negative thermodynamic temperature, and added a provision to allow t...

[Phys. Rev. Lett. 120, 250602] Published Thu Jun 21, 2018

Categories: Journals, Physics

Nested Transition Path Sampling

Wed, 2018-06-20 12:00

Author(s): Peter G. Bolhuis and Gábor Csányi

We introduce a novel transition path (TPS) sampling scheme employing nested sampling. Analogous to how nested sampling explores the entire configurational phase space for atomistic systems, nested TPS samples the entire available trajectory space in one simulation. Thermodynamic and path observables...

[Phys. Rev. Lett. 120, 250601] Published Wed Jun 20, 2018

Categories: Journals, Physics

Characterization of Topological States via Dual Multipartite Entanglement

Mon, 2018-06-18 12:00

Author(s): Yu-Ran Zhang, Yu Zeng, Heng Fan, J. Q. You, and Franco Nori

We demonstrate that multipartite entanglement is able to characterize one-dimensional symmetry-protected topological order, which is witnessed by the scaling behavior of the quantum Fisher information of the ground state with respect to the spin operators defined in the dual lattice. We investigate ...

[Phys. Rev. Lett. 120, 250501] Published Mon Jun 18, 2018

Categories: Journals, Physics