Experimental observation of the Yang-Lee quantum criticality in open systems

• URL: http://arxiv.org/abs/2312.01706v1
• Date: Mon, 4 Dec 2023 07:50:45 GMT
• Title: Experimental observation of the Yang-Lee quantum criticality in open systems
• Authors: Huixia Gao, Kunkun Wang, Lei Xiao, Masaya Nakagawa, Norifumi Matsumoto, Dengke Qu, Haiqing Lin, Masahito Ueda, Peng Xue
• Abstract summary: We experimentally implement an imaginary magnetic field and demonstrate the Yang-Lee edge singularity through a nonunitary evolution governed by a non-Hermitian Hamiltonian in an open quantum system. We also demonstrate unconventional scaling laws for the finite-temperature dynamics unique to quantum systems.
• Score: 12.706586603485578
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: The Yang-Lee edge singularity was originally studied from the standpoint of mathematical foundations of phase transitions, and its physical demonstration has been of active interest both theoretically and experimentally. However, the presence of an imaginary magnetic field in the Yang-Lee edge singularity has made it challenging to develop a direct observation of the anomalous scaling with negative scaling dimension associated with this critical phenomenon. We experimentally implement an imaginary magnetic field and demonstrate the Yang-Lee edge singularity through a nonunitary evolution governed by a non-Hermitian Hamiltonian in an open quantum system, where a classical system is mapped to a quantum system via the equivalent canonical partition function. In particular, we directly observe the partition function in our experiment using heralded single photons. The nonunitary quantum criticality is identified with the singularity at an exceptional point. We also demonstrate unconventional scaling laws for the finite-temperature dynamics unique to quantum systems.

Related papers

• Anisotropy-induced spin parity effects [0.0]
  A dichotomy in the physical behavior of a system arises, solely depending on whether the relevant spin quantum number is integral or half-odd integral. Here, we put forth a simple and general scheme for generating such effects in any spatial dimension through the use of anisotropic interactions. We demonstrate its utility through a detailed analysis of the magnetization behavior of a specific one-dimensional spin chain model, an anisotropic antiferromagnet in a transverse magnetic field.
  arXiv  Detail & Related papers  (2024-02-29T16:15:43Z)
• Parametrically driving a quantum oscillator into exceptionality [0.0]
  We consider the nature of exceptional points arising in quantum systems described within an open quantum systems approach. In particular, we discuss how the populations, correlations, squeezed quadratures and optical spectra crucially depend on being above or below the exceptional point. Our results invite the experimental probing of quantum resonators under two-photon driving.
  arXiv  Detail & Related papers  (2023-07-07T13:27:20Z)
• Universality of critical dynamics with finite entanglement [68.8204255655161]
  We study how low-energy dynamics of quantum systems near criticality are modified by finite entanglement. Our result establishes the precise role played by entanglement in time-dependent critical phenomena.
  arXiv  Detail & Related papers  (2023-01-23T19:23:54Z)
• Non-Abelian braiding of graph vertices in a superconducting processor [144.97755321680464]
  Indistinguishability of particles is a fundamental principle of quantum mechanics. braiding of non-Abelian anyons causes rotations in a space of degenerate wavefunctions. We experimentally verify the fusion rules of the anyons and braid them to realize their statistics.
  arXiv  Detail & Related papers  (2022-10-19T02:28:44Z)
• Demonstrating Quantum Microscopic Reversibility Using Coherent States of Light [58.8645797643406]
  We propose and experimentally test a quantum generalization of the microscopic reversibility when a quantum system interacts with a heat bath. We verify that the quantum modification for the principle of microscopic reversibility is critical in the low-temperature limit.
  arXiv  Detail & Related papers  (2022-05-26T00:25:29Z)
• Embedding the Yang-Lee Quantum Criticality in Open Quantum Systems [4.511923587827301]
  The Yang-Lee edge singularity is a quintessential nonunitary critical phenomenon accompanied by anomalous scaling laws. By invoking the quantum-classical correspondence, we demonstrate a physical realization of the nonunitary quantum criticality in an open quantum system.
  arXiv  Detail & Related papers  (2020-12-24T07:08:55Z)
• Emergence of the Born rule in quantum optics [0.0]
  The Born rule provides a fundamental connection between theory and observation in quantum mechanics, yet its origin remains a mystery. We consider this problem using only classical physics and the assumption of a quantum electrodynamic vacuum that is real rather than virtual. The connection to observation is made via classical intensity threshold detectors that are used as a simple, deterministic model of photon detection.
  arXiv  Detail & Related papers  (2020-04-19T02:24:22Z)
• Quantum Zeno effect appears in stages [64.41511459132334]
  In the quantum Zeno effect, quantum measurements can block the coherent oscillation of a two level system by freezing its state to one of the measurement eigenstates. We show that the onset of the Zeno regime is marked by a $textitcascade of transitions$ in the system dynamics as the measurement strength is increased.
  arXiv  Detail & Related papers  (2020-03-23T18:17:36Z)
• Theory of waveguide-QED with moving emitters [68.8204255655161]
  We study a system composed by a waveguide and a moving quantum emitter in the single excitation subspace. We first characterize single-photon scattering off a single moving quantum emitter, showing both nonreciprocal transmission and recoil-induced reduction of the quantum emitter motional energy.
  arXiv  Detail & Related papers  (2020-03-20T12:14:10Z)
• Dynamically encircling an exceptional point in a real quantum system [13.510562179346167]
  The exceptional point, known as the non-Hermitian degeneracy, has special topological structure. Here we experimentally demonstrate dynamically encircling the exceptional point with a single nitrogen-vacancy center in diamond. Our work reveals the topological structure of the exceptional point and paves the way to comprehensively explore the exotic properties of non-Hermitian Hamiltonians in the quantum regime.
  arXiv  Detail & Related papers  (2020-02-17T06:41:17Z)
• Einselection from incompatible decoherence channels [62.997667081978825]
  We analyze an open quantum dynamics inspired by CQED experiments with two non-commuting Lindblad operators. We show that Fock states remain the most robust states to decoherence up to a critical coupling.
  arXiv  Detail & Related papers  (2020-01-29T14:15:19Z)

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.