Decoherence Induced Exceptional Points in a Dissipative Superconducting Qubit

• URL: http://arxiv.org/abs/2111.04754v1
• Date: Mon, 8 Nov 2021 19:00:02 GMT
• Title: Decoherence Induced Exceptional Points in a Dissipative Superconducting Qubit
• Authors: Weijian Chen, Maryam Abbasi, Byung Ha, Serra Erdamar, Yogesh N. Joglekar, and Kater W. Murch
• Abstract summary: Open quantum systems interacting with an environment exhibit dynamics described by the combination of dissipation and coherent Hamiltonian evolution. The degeneracies of the (generically non-Hermitian) Liouvillian are exceptional points, which are associated with critical dynamics as the system approaches steady state. We use a superconducting transmon circuit coupled to an engineered environment to observe two different types of Liouvillian exceptional points that arise either from the interplay of energy loss and decoherence or purely due to decoherence.
• Score: 0.31171750528972203
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Open quantum systems interacting with an environment exhibit dynamics described by the combination of dissipation and coherent Hamiltonian evolution. Taken together, these effects are captured by a Liouvillian superoperator. The degeneracies of the (generically non-Hermitian) Liouvillian are exceptional points, which are associated with critical dynamics as the system approaches steady state. We use a superconducting transmon circuit coupled to an engineered environment to observe two different types of Liouvillian exceptional points that arise either from the interplay of energy loss and decoherence or purely due to decoherence. By dynamically tuning the Liouvillian superoperators in real time we observe a non-Hermiticity-induced chiral state transfer. Our study motivates a new look at open quantum system dynamics from the vantage of Liouvillian exceptional points, enabling applications of non-Hermitian dynamics in the understanding and control of open quantum systems.

Related papers

• Encircling the Liouvillian exceptional points: a brief review [1.5596062401801003]
  Liouvillian exceptional points often have distinct properties compared to their counterparts in non-Hermitian Hamiltonians. Since the Liouvillian exceptional points widely exist in quantum systems such as the atomic vapours, superconducting qubits, and ultracold ions and atoms, they have received increasing amount of attention of late.
  arXiv  Detail & Related papers  (2024-08-21T08:46:04Z)
• Crossing exceptional points in non-Hermitian quantum systems [41.94295877935867]
  We reveal the behavior of two-photon quantum states in non-Hermitian systems across the exceptional point. We demonstrate a switching in the quantum interference of photons directly at the exceptional point.
  arXiv  Detail & Related papers  (2024-07-17T14:04:00Z)
• Magnetization in a non-equilibrium quantum spin system [0.0]
  We show that the effective non-Hermitian Hamiltonian can accurately represent the long-term dynamics of a critical two-level open quantum system. The NESS is identical to the coalescent state of the effective non-Hermitian Hamiltonian. This discovery paves the way for a better understanding of the long-term dynamics of critical open quantum systems.
  arXiv  Detail & Related papers  (2024-06-01T02:16:24Z)
• Non-equilibrium quantum probing through linear response [41.94295877935867]
  We study the system's response to unitary perturbations, as well as non-unitary perturbations, affecting the properties of the environment. We show that linear response, combined with a quantum probing approach, can effectively provide valuable quantitative information about the perturbation and characteristics of the environment.
  arXiv  Detail & Related papers  (2023-06-14T13:31:23Z)
• Chiral state transfer under dephasing [0.228438857884398]
  We study the effects of dephasing on the encircling dynamics, adopting the full Lindblad master equation. We show that gaps emerge in the eigenspectra landscape of the corresponding Liouvillian superoperator. While our results are applicable to several recent experiments, we examine a recent cold-atom experiment in particular, and show that the observed long-time chirality is but limited to the special encircling path therein.
  arXiv  Detail & Related papers  (2022-12-25T07:18:33Z)
• Effective Hamiltonian theory of open quantum systems at strong coupling [0.0]
  We present the reaction-coordinate polaron-transform (RCPT) framework for generating effective Hamiltonian models. Examples in this work include canonical models for quantum thermalization, charge and energy transport at the nanoscale, performance bounds of quantum thermodynamical machines.
  arXiv  Detail & Related papers  (2022-11-10T17:10:33Z)
• Decimation technique for open quantum systems: a case study with driven-dissipative bosonic chains [62.997667081978825]
  Unavoidable coupling of quantum systems to external degrees of freedom leads to dissipative (non-unitary) dynamics. We introduce a method to deal with these systems based on the calculation of (dissipative) lattice Green's function. We illustrate the power of this method with several examples of driven-dissipative bosonic chains of increasing complexity.
  arXiv  Detail & Related papers  (2022-02-15T19:00:09Z)
• From geometry to coherent dissipative dynamics in quantum mechanics [68.8204255655161]
  We work out the case of finite-level systems, for which it is shown by means of the corresponding contact master equation. We describe quantum decays in a 2-level system as coherent and continuous processes.
  arXiv  Detail & Related papers  (2021-07-29T18:27:38Z)
• Intrinsic mechanisms for drive-dependent Purcell decay in superconducting quantum circuits [68.8204255655161]
  We find that in a wide range of settings, the cavity-qubit detuning controls whether a non-zero photonic population increases or decreases qubit decay Purcell. Our method combines insights from a Keldysh treatment of the system, and Lindblad theory.
  arXiv  Detail & Related papers  (2021-06-09T16:21:31Z)
• Dissipative dynamics of an open quantum battery [0.0]
  Coupling with an external environment inevitably affects the dynamics of a quantum system. We consider how charging performances of a quantum battery, modelled as a two level system, are influenced by the presence of an Ohmic thermal reservoir.
  arXiv  Detail & Related papers  (2020-05-28T14:11:38Z)
• 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.