Bures and Sjoqvist Metrics over Thermal State Manifolds for Spin Qubits and Superconducting Flux Qubits

• URL: http://arxiv.org/abs/2303.01680v1
• Date: Fri, 3 Mar 2023 02:48:00 GMT
• Title: Bures and Sjoqvist Metrics over Thermal State Manifolds for Spin Qubits and Superconducting Flux Qubits
• Authors: Carlo Cafaro, Paul M. Alsing
• Abstract summary: We present an explicit analysis of the Bures and Sjoqvist metrics over the inverse of thermal states for specific spin qubit and the superconducting flux qubit Hamiltonian models. We conclude the two metrics differ in the presence of a nonclassical behavior specified by the noncommutativity of neighboring mixed quantum states.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: The interplay among differential geometry, statistical physics, and quantum information science has been increasingly gaining theoretical interest in recent years. In this paper, we present an explicit analysis of the Bures and Sjoqvist metrics over the manifolds of thermal states for specific spin qubit and the superconducting flux qubit Hamiltonian models. While the two metrics equally reduce to the Fubini-Study metric in the asymptotic limiting case of the inverse temperature approaching infinity for both Hamiltonian models, we observe that the two metrics are generally different when departing from the zero-temperature limit. In particular, we discuss this discrepancy in the case of the superconducting flux Hamiltonian model. We conclude the two metrics differ in the presence of a nonclassical behavior specified by the noncommutativity of neighboring mixed quantum states. Such a noncommutativity, in turn, is quantified by the two metrics in different manners. Finally, we briefly discuss possible observable consequences of this discrepancy between the two metrics when using them to predict critical and/or complex behavior of physical systems of interest in quantum information science.

Related papers

• 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)
• Evolution of many-body systems under ancilla quantum measurements [58.720142291102135]
  We study the concept of implementing quantum measurements by coupling a many-body lattice system to an ancillary degree of freedom. We find evidence of a disentangling-entangling measurement-induced transition as was previously observed in more abstract models.
  arXiv  Detail & Related papers  (2023-03-13T13:06:40Z)
• Comparing metrics for mixed quantum states: Sjoqvist and Bures [3.3873470587012893]
  We discuss the relation between the Sjoqvist metric and the Bures metric for arbitrary nondegenerate mixed quantum states. We show the difference between these two metrics in the case of a simple physical system characterized by a spin-qubit in an arbitrarily oriented uniform.
  arXiv  Detail & Related papers  (2023-03-03T03:08:04Z)
• Observation of partial and infinite-temperature thermalization induced by repeated measurements on a quantum hardware [62.997667081978825]
  We observe partial and infinite-temperature thermalization on a quantum superconducting processor. We show that the convergence does not tend to a completely mixed (infinite-temperature) state, but to a block-diagonal state in the observable basis.
  arXiv  Detail & Related papers  (2022-11-14T15:18:11Z)
• Non-Abelian symmetry can increase entanglement entropy [62.997667081978825]
  We quantify the effects of charges' noncommutation on Page curves. We show analytically and numerically that the noncommuting-charge case has more entanglement.
  arXiv  Detail & Related papers  (2022-09-28T18:00:00Z)
• Quantum chaos and thermalization in the two-mode Dicke model [77.34726150561087]
  We discuss the onset of quantum chaos and thermalization in the two-mode Dicke model. The two-mode Dicke model exhibits normal to superradiant quantum phase transition. We show that the temporal fluctuations of the expectation value of the collective spin observable around its average are small and decrease with the effective system size.
  arXiv  Detail & Related papers  (2022-07-08T11:16:29Z)
• Energy fluctuation relations and repeated quantum measurements [4.724825031148412]
  We discuss the statistical description in non-equilibrium regimes of energy fluctuations originated by the interaction between a quantum system and a measurement apparatus. To properly quantify the information about energy fluctuations, both the exchanged heat probability density function and the corresponding characteristic function are derived and interpreted.
  arXiv  Detail & Related papers  (2022-02-05T16:20:13Z)
• Classical description of the parameter space geometry in the Dicke and Lipkin-Meshkov-Glick models [0.0]
  We study the classical analog of the quantum metric tensor and its scalar curvature for two well-known quantum physics models. We find that, in the thermodynamic limit, they have the same divergent behavior near the quantum phase transition. We also show that the scalar curvature is only defined on one of the system's phases and that it approaches a negative constant value.
  arXiv  Detail & Related papers  (2021-07-12T22:11:45Z)
• Hamiltonian Model for Fault Tolerant Singlet-Like Excitation: First Principles Approach [0.0]
  We investigate the reduced state of two qubits coupled to each other via a common heat bath of linear harmonics. We search for evidence of fault-tolerant excited qubit states. We emphasize the central role of the Lambshift as an agent responsible for fault tolerant excitations.
  arXiv  Detail & Related papers  (2021-05-20T14:14:00Z)
• Evolution of a Non-Hermitian Quantum Single-Molecule Junction at Constant Temperature [62.997667081978825]
  We present a theory for describing non-Hermitian quantum systems embedded in constant-temperature environments. We find that the combined action of probability losses and thermal fluctuations assists quantum transport through the molecular junction.
  arXiv  Detail & Related papers  (2021-01-21T14:33:34Z)

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.