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Related papers: Probing Quantum Speed Limits with Ultracold Gases

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Speed of state transitions in macroscopic systems is a crucial concept for foundations of nonequilibrium statistical mechanics as well as various applications in quantum technology represented by optimal quantum control. While extensive…

Statistical Mechanics · Physics 2022-04-29 Ryusuke Hamazaki

In this study, we investigate the bound on the speed of state transformation in the quantum and classical systems that are coupled to general environment with arbitrary coupling interactions. We show that a Mandelstam-Tamm type speed limit…

Statistical Mechanics · Physics 2021-05-05 Naoto Shiraishi , Keiji Saito

We evaluate a Gaussian entanglement measure for a symmetric two-mode Gaussian state of the quantum electromagnetic field in terms of its Bures distance to the set of all separable Gaussian states. The required minimization procedure was…

Quantum Physics · Physics 2009-11-13 Paulina Marian , Tudor A. Marian

The question of how fast a quantum state can evolve has attracted a considerable attention in connection with quantum measurement, metrology, and information processing. Since only orthogonal states can be unambiguously distinguished, a…

Quantum Physics · Physics 2015-05-13 Lev B. Levitin , Tommaso Toffoli

The time evolution of cosmological parameters in early Universe at the deconfinement transition is studied by an equation of state (EoS) which takes into account the finite baryon density and the background magnetic field. The non…

High Energy Physics - Phenomenology · Physics 2015-09-30 Paolo Castorina , Vincenzo Greco , Salvatore Plumari

The quantum speed limit specifies a universal bound of the fidelity between the initial state and the time-evolved state. We apply this method to find a bound of the fidelity between the adiabatic state and the time-evolved state. The bound…

Quantum Physics · Physics 2020-07-22 Keisuke Suzuki , Kazutaka Takahashi

Important properties of a quantum system are not directly measurable, but they can be disclosed by how fast the system changes under controlled perturbations. In particular, asymmetry and entanglement can be verified by reconstructing the…

The question of how fast a quantum state can evolve is considered. Using the definition of squared speed based on the Euclidean distance given in [Phys. Rev. Research, {\bf 2}, 033127 (2019)], we present a systematic framework to obtain the…

Quantum Physics · Physics 2024-02-05 Ashraf Naderzadeh-ostad , Seyed Javad Akhtarshenas

Quantum phase slips are the primary excitations in one-dimensional superfluids and superconductors at low temperatures but their existence in ultracold quantum gases has not been demonstrated yet. We now study experimentally the nucleation…

We show that nonorthogonal states achieve a higher level of entanglement when one party undergoes uniform acceleration. We also show that in this regime non-orthogonal states achieve a higher fidelity for teleportation. A quantum field as…

Quantum Physics · Physics 2012-10-12 G. A. White

The behavior of quantum speed limit time (QSLT) for a single free spin $-1/2$ particle described by Gaussian wavepackets in the framework of relativity under dephasing noise is investigated. The dephasing noise acts only on the spin degrees…

Quantum Physics · Physics 2016-12-22 Salman Khan , Niaz Ali Khan

Ultrafast electronic dynamics are typically studied using pulsed lasers. We demonstrate a complementary experimental approach: quantum simulation of ultrafast dynamics using trapped ultracold atoms. Counter-intuitively, this technique…

We investigate the number fluctuations in small cells of quantum gases pointing out important deviations from the thermodynamic limit fixed by the isothermal compressibility. Both quantum and thermal fluctuations in weakly as well as highly…

Quantum Gases · Physics 2011-09-30 M. Klawunn , A. Recati , L. P. Pitaevskii , S. Stringari

We present a geometric optimization method for implementing quantum gates by optimally controlling the Hamiltonian parameters, with the goal of approaching the Mandelstam-Tamm Quantum Speed Limit (MT-QSL). Achieving this bound requires…

Quantum Physics · Physics 2025-11-06 F. Impens , D. Guéry-Odelin

The quantum speed limit and the Wigner function of open system models are studied. To this end, we use the phase covariant and a two-qubit model interacting with a squeezed thermal bath via position-dependent coupling. The dependence of the…

Quantum Physics · Physics 2025-04-18 Arti Gaharwar , Devvrat Tiwari , Subhashish Banerjee

Fastness and robustness are both critical in the implementation of high-fidelity gates for quantum computation, but in practice, a trade-off has to be made between them. In this paper, we investigate the underlying robust time-optimal…

Quantum Physics · Physics 2023-09-12 Xi Cao , Jiangyu Cui , Man Hong Yung , Re-Bing Wu

Quantum fluctuations in an ultrafast rotating Bose gas at zero temperature are investigated. We calculate the condensate density perturbatively to show that no condensate is present in the thermodynamic limit. The excitation from Gaussian…

Quantum Gases · Physics 2013-05-29 Qiong Li , Bo Feng , Dingping Li

Quantum fluctuations or other moments of a state contribute to energy expectation values and can imply interesting physical effects. In quantum cosmology, they turn out to be important for a discussion of density bounds and instabilities of…

General Relativity and Quantum Cosmology · Physics 2014-07-02 Martin Bojowald

How fast an observable can evolve in time is answered by so-called ``observable speed limit". Here, we prove a stronger version of the observable speed limit and show that the previously obtained bound is a special case of the new bound.…

Quantum Physics · Physics 2024-12-09 Divyansh Shrimali , Biswaranjan Panda , Arun Kumar Pati

We calculate the time evolution of a far-from-equilibrium initial state of a non-relativistic ultracold Bose gas in one spatial dimension. The non-perturbative approximation scheme is based on a systematic expansion of the two-particle…

Other Condensed Matter · Physics 2008-11-26 T. Gasenzer , J. Berges , M. G. Schmidt , M. Seco