Superflow decay in a toroidal Bose gas: The effect of quantum and thermal fluctuations

• URL: http://arxiv.org/abs/2105.03154v4
• Date: Sun, 31 Oct 2021 06:56:40 GMT
• Title: Superflow decay in a toroidal Bose gas: The effect of quantum and thermal fluctuations
• Authors: Zain Mehdi, Ashton S. Bradley, Joseph J. Hope, Stuart S. Szigeti
• Abstract summary: We theoretically investigate the decay of persistent currents in a toroidal atomic supercold caused by a perturbing barrier. Our results suggest a need for further experimental and theoretical studies into superflow stability.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We theoretically investigate the stochastic decay of persistent currents in a toroidal ultracold atomic superfluid caused by a perturbing barrier. Specifically, we perform detailed three-dimensional simulations to model the experiment of Kumar et al. in [Phys. Rev. A 95 021602 (2017)], which observed a strong temperature dependence in the timescale of superflow decay in an ultracold Bose gas. Our ab initio numerical approach exploits a classical-field framework that includes thermal fluctuations due to interactions between the superfluid and a thermal cloud, as well as the intrinsic quantum fluctuations of the Bose gas. In the low-temperature regime our simulations provide a quantitative description of the experimental decay timescales, improving on previous numerical and analytical approaches. At higher temperatures, our simulations give decay timescales that range over the same orders of magnitude observed in the experiment, however, there are some quantitative discrepancies that are not captured by any of the mechanisms we explore. Our results suggest a need for further experimental and theoretical studies into superflow stability.

Related papers

• Revisiting Joule-expansion experiments with a quantum gas [0.0]
  We revisit the classic Joule-expansion experiments, now with a quantum-degenerate atomic Bose gas. In contrast to the classical-gas experiments, where no temperature change was measured, here we observe both cooling and heating effects.
  arXiv  Detail & Related papers  (2024-10-31T17:59:46Z)
• Stability of superfluids in tilted optical lattices with periodic driving [0.0]
  We experimentally investigate phonon modes and interaction-driven instabilities of superfluids in the lowest band of a shaken optical lattice. Our observations enable the prediction of stable parameter regimes for quantum-simulation experiments.
  arXiv  Detail & Related papers  (2024-01-10T16:46:34Z)
• Quantum Effects on the Synchronization Dynamics of the Kuramoto Model [62.997667081978825]
  We show that quantum fluctuations hinder the emergence of synchronization, albeit not entirely suppressing it. We derive an analytical expression for the critical coupling, highlighting its dependence on the model parameters.
  arXiv  Detail & Related papers  (2023-06-16T16:41:16Z)
• Optical self-cooling of a membrane oscillator in a cavity optomechanical experiment at room temperature [0.0]
  Thermal noise is a major obstacle to observing quantum behavior in macroscopic systems. We show that further cooling is prevented by the excess classical noise of our laser source.
  arXiv  Detail & Related papers  (2023-05-24T08:56:23Z)
• Dynamics of molecular rotors in bulk superfluid helium [68.8204255655161]
  We report on the experimental study of the laser-induced rotation of helium dimers inside the superfluid $4mathrmHe$ bath at variable temperature. The observed temperature dependence suggests a non-equilibrium evolution of the quantum bath, accompanied by the emission of the wave of second sound.
  arXiv  Detail & Related papers  (2023-04-08T01:22:19Z)
• Probing finite-temperature observables in quantum simulators of spin systems with short-time dynamics [62.997667081978825]
  We show how finite-temperature observables can be obtained with an algorithm motivated from the Jarzynski equality. We show that a finite temperature phase transition in the long-range transverse field Ising model can be characterized in trapped ion quantum simulators.
  arXiv  Detail & Related papers  (2022-06-03T18:00:02Z)
• Taking the temperature of a pure quantum state [55.41644538483948]
  Temperature is a deceptively simple concept that still raises deep questions at the forefront of quantum physics research. We propose a scheme to measure the temperature of such pure states through quantum interference.
  arXiv  Detail & Related papers  (2021-03-30T18:18:37Z)
• Analog cosmological reheating in an ultracold Bose gas [58.720142291102135]
  We quantum-simulate the reheating-like dynamics of a generic cosmological single-field model in an ultracold Bose gas. Expanding spacetime as well as the background oscillating inflaton field are mimicked in the non-relativistic limit. The proposed experiment has the potential of exploring the evolution up to late times even beyond the weak coupling regime.
  arXiv  Detail & Related papers  (2020-08-05T18:00:26Z)
• Probing eigenstate thermalization in quantum simulators via fluctuation-dissipation relations [77.34726150561087]
  The eigenstate thermalization hypothesis (ETH) offers a universal mechanism for the approach to equilibrium of closed quantum many-body systems. Here, we propose a theory-independent route to probe the full ETH in quantum simulators by observing the emergence of fluctuation-dissipation relations. Our work presents a theory-independent way to characterize thermalization in quantum simulators and paves the way to quantum simulate condensed matter pump-probe experiments.
  arXiv  Detail & Related papers  (2020-07-20T18:00:02Z)
• Asymptotic States of Accelerated Qubits with Nonzero Background Temperature [0.0]
  The study of the Unruh effect naturally raises the interest for a deeper understanding of the analogy between temperature and acceleration. We use the open quantum system formalism to investigate the case where both acceleration and background temperature are present.
  arXiv  Detail & Related papers  (2020-02-05T22:18:51Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.