Continuous time crystals as a PT symmetric state and the emergence of critical exceptional points

• URL: http://arxiv.org/abs/2406.09018v1
• Date: Thu, 13 Jun 2024 11:43:45 GMT
• Title: Continuous time crystals as a PT symmetric state and the emergence of critical exceptional points
• Authors: Yuma Nakanishi, Ryo Hanai, Tomohiro Sasamoto,
• Abstract summary: We show that a Lindladian parity-time symmetry can generically produce persistent periodic oscillations. The periodic orbits in the PT-symmetric phase are found to be center-type, implying an initial-state-dependent amplitude. This research will further our understanding of novel non-equilibrium phases of matter and phase transitions with spontaneous anti-unitary symmetry breaking.
• Score: 0.7373617024876725
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Continuous time-translation symmetry is often spontaneously broken in open quantum systems, and the condition for their emergence has been actively investigated. However, there are only a few cases in which its condition for appearance has been fully elucidated. In this Letter, we show that a Lindladian parity-time (PT) symmetry can generically produce persistent periodic oscillations, including dissipative continuous time crystals, in one-collective spin models. By making an analogy to non-reciprocal phase transitions, we demonstrate that a transition point from the dynamical phase is associated with spontaneous PT symmetry breaking and typically corresponds to a \textit{critical exceptional point}. Interestingly, the periodic orbits in the PT-symmetric phase are found to be center-type, implying an initial-state-dependent amplitude. These results are established by proving that the Lindbladian PT symmetry at the microscopic level implies a non-linear PT symmetry, and by performing a linear stability analysis near the transition point. This research will further our understanding of novel non-equilibrium phases of matter and phase transitions with spontaneous anti-unitary symmetry breaking.

Related papers

• Measurement-induced entanglement transition in chaotic quantum Ising chain [42.87502453001109]
  We study perturbations that break the integrability and/or the symmetry of the model, as well as modifications in the measurement protocol, characterizing the resulting chaos and lack of integrability through the Dissipative Spectral Form Factor (DSFF) We show that while the measurement-induced phase transition and its properties appear broadly insensitive to lack of integrability and breaking of the $bbZ$ symmetry, a modification of the measurement basis from the transverse to the longitudinal direction makes the phase transition disappear altogether.
  arXiv  Detail & Related papers  (2024-07-11T17:39:29Z)
• Revealing spontaneous symmetry breaking in continuous time crystals [17.62738825431278]
  Spontaneous symmetry breaking leads to a novel state of matter named continuous time crystal (CTC) We propose and experimentally realize two types of CTCs based on distinct mechanisms: manifold topology and near-chaotic motion. Our work provides general recipes for the realization of CTCs, and paves the way for exploring CTCs in various systems.
  arXiv  Detail & Related papers  (2024-07-10T14:27:06Z)
• Topological Phases in a PT-Symmetric Dissipative Kitaev Chain [0.0]
  We study a topological phase in the dissipative Kitaev chain described by the Markovian quantum master equation. We find out that the Lindbladian retains PT symmetry which is the prominent symmetry of open systems.
  arXiv  Detail & Related papers  (2023-01-20T06:53:46Z)
• Entanglement entropy distinguishes PT-symmetry and topological phases in a class of non-unitary quantum walks [0.0]
  We calculate the hybrid entanglement entropy between coin and walker degrees of freedom in a non-unitary quantum walk. An analysis at long times reveals that the quantum walk can indefinitely sustain hybrid entanglement in the unbroken symmetry phase even when gain and loss mechanisms are present.
  arXiv  Detail & Related papers  (2022-12-14T19:01:15Z)
• Clean two-dimensional Floquet time-crystal [68.8204255655161]
  We consider the two-dimensional quantum Ising model, in absence of disorder, subject to periodic imperfect global spin flips. We show by a combination of exact diagonalization and tensor-network methods that the system can sustain a spontaneously broken discrete time-translation symmetry. We observe a non-perturbative change in the decay rate of the order parameter, which is related to the long-lived stability of the magnetic domains in 2D.
  arXiv  Detail & Related papers  (2022-05-10T13:04:43Z)
• Exact solution of a boundary time-crystal phase transition: time-translation symmetry breaking and non-Markovian dynamics of correlations [0.0]
  Systems that display nonequilibrium transitions into these phases are referred to as time-crystals. We show that boundary time-crystals are intrinsically critical phases, where fluctuations exhibit a power-law divergence with time.
  arXiv  Detail & Related papers  (2021-09-30T18:00:10Z)
• Observation of a symmetry-protected topological time crystal with superconducting qubits [14.264932047880043]
  We report the observation of a symmetry-protected topological time crystal implemented with an array of programmable superconducting qubits. We observe robust long-lived temporal correlations and sub-harmonic temporal response for the edge spins up to 40 driving cycles. Our work paves the way to exploring peculiar non-equilibrium phases of matter emerged from the interplay between topology and localization as well as periodic driving.
  arXiv  Detail & Related papers  (2021-09-12T18:00:03Z)
• Observation of Time-Crystalline Eigenstate Order on a Quantum Processor [80.17270167652622]
  Quantum-body systems display rich phase structure in their low-temperature equilibrium states. We experimentally observe an eigenstate-ordered DTC on superconducting qubits. Results establish a scalable approach to study non-equilibrium phases of matter on current quantum processors.
  arXiv  Detail & Related papers  (2021-07-28T18:00:03Z)
• Quotient symmetry protected topological phenomena [0.0]
  We show that topological phenomena can be stable over a large part of parameter space even when the bulk is strictly speaking in a trivial phase of matter. Although the Haldane phase is then adiabatically connected to a product state, we show that characteristic phenomena -- edge modes, entanglement degeneracies and bulk phase transitions -- remain parametrically stable.
  arXiv  Detail & Related papers  (2021-02-17T19:00:04Z)
• Spontaneous and explicit parity-time-symmetry breaking in drift wave instabilities [84.14613391584454]
  We show that spontaneous PT-symmetry breaking leads to the Ion Temperature Gradient (ITG) instability of drift waves, and the collisional instability is the result of explicit PT-symmetry breaking. It is also found that gradients of ion temperature and density can destabilize the ion cyclotron waves when PT symmetry is explicitly broken by a finite collisionality.
  arXiv  Detail & Related papers  (2020-10-19T15:59:12Z)
• Observation of Hermitian and Non-Hermitian Diabolic Points and Exceptional Rings in Parity-Time symmetric ZRC and RLC Dimers [62.997667081978825]
  We show how appears non-Hermitian degeneracy points in the spectrum and how they are protected against a Hermitian perturbation. This work opens a gold road for investigations on topological electrical circuits for robust transport of information at room temperature.
  arXiv  Detail & Related papers  (2020-04-17T15:51:49Z)

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.