Characterization of partially accessible anisotropic spin chains in the presence of anti-symmetric exchange

• URL: http://arxiv.org/abs/2401.14479v1
• Date: Thu, 25 Jan 2024 19:26:35 GMT
• Title: Characterization of partially accessible anisotropic spin chains in the presence of anti-symmetric exchange
• Authors: Simone Cavazzoni, Marco Adani, Paolo Bordone, Matteo G. A. Paris
• Abstract summary: We address quantum characterization of anisotropic spin chains in the presence of antisymmetric exchange. We investigate whether the Hamiltonian parameters of the chain may be estimated with precision approaching the ultimate limit imposed by quantum mechanics.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We address quantum characterization of anisotropic spin chains in the presence of antisymmetric exchange, and investigate whether the Hamiltonian parameters of the chain may be estimated with precision approaching the ultimate limit imposed by quantum mechanics. At variance with previous approaches, we focus on the information that may be extracted by measuring only two neighbouring spins rather than a global observable on the entire chain. We evaluate the Fisher information (FI) of a two-spin magnetization measure, and the corresponding quantum Fisher information (QFI), for all the relevant parameters, i.e. the spin coupling, the anisotropy, and the Dzyaloshinskii Moriya (DM) parameter. Our results show that the reduced system made of two neighbouring spins may be indeed exploited as a probe to characterize global properties of the entire system. In particular, we find that the ratio between the FI and the QFI is close to unit for a large range of the coupling values. The DM coupling is beneficial for coupling estimation, since it leads to the presence of additional bumps and peaks in the FI and QFI, which are not present in a model that neglects exchange interaction and may be exploited to increase the robustness of the overall estimation procedure. Finally, we address the multiparameter estimation problem, and show that the model is compatible but sloppy, i.e. both the Uhlmann curvature and the determinant of the QFI matrix vanish. Physically, this means that the state of the system actually depends only on a reduced numbers of combinations of parameters, and not on all of them separately.

Related papers

• Multicritical quantum sensors driven by symmetry-breaking [0.7499722271664147]
  We analytically demonstrate that symmetry-breaking can drive a quantum enhanced sensing in single- or multi parameter estimation. We show that it is possible to obtain super-Heisenberg scaling by combining the effects of symmetry-breaking and gapless-to-gapped transition.
  arXiv  Detail & Related papers  (2024-07-19T15:57:02Z)
• Critical metrology of minimally accessible anisotropic spin chains [0.0]
  We show how local and quasi-local measurements may be exploited to characterize global properties of the systems. In particular, we evaluate the classical (magnetization) and quantum Fisher information of the relevant parameters for the density matrix of a single spin.
  arXiv  Detail & Related papers  (2024-05-30T17:45:27Z)
• Theory of free fermions dynamics under partial post-selected monitoring [49.1574468325115]
  We derive a partial post-selected Schrdinger"o equation based on a microscopic description of continuous weak measurement. We show that the passage to the monitored universality occurs abruptly at finite partial post-selection. Our approach establishes a way to study MiPTs for arbitrary subsets of quantum trajectories.
  arXiv  Detail & Related papers  (2023-12-21T16:53:42Z)
• Multiparameter critical quantum metrology with impurity probes [0.0]
  We introduce the two-impurity Kondo (2IK) model as a novel paradigm for critical quantum metrology. We demonstrate that by applying a known control field, the singularity can be removed and measurement sensitivity restored.
  arXiv  Detail & Related papers  (2023-11-28T16:32:51Z)
• Ancilla quantum measurements on interacting chains: Sensitivity of entanglement dynamics to the type and concentration of detectors [46.76612530830571]
  We consider a quantum many-body lattice system that is coupled to ancillary degrees of freedom (detectors'') We explore the dynamics of density and of entanglement entropy in the chain, for various values of $rho_a$ and $M$.
  arXiv  Detail & Related papers  (2023-11-21T21:41:11Z)
• Quantum metrology enhanced by the $XY$ spin interaction in a generalized Tavis-Cummings model [0.0]
  We explore the impact of the many-body effect on estimation precision, quantified by the quantum Fisher information (QFI) We emphasize the indispensable role of the spin anisotropy in achieving the Heisenberg-scaling precision.
  arXiv  Detail & Related papers  (2023-07-30T08:20:26Z)
• 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)
• Gate-based spin readout of hole quantum dots with site-dependent $g-$factors [101.23523361398418]
  We experimentally investigate a hole double quantum dot in silicon by carrying out spin readout with gate-based reflectometry. We show that characteristic features in the reflected phase signal arising from magneto-spectroscopy convey information on site-dependent $g-$factors in the two dots.
  arXiv  Detail & Related papers  (2022-06-27T09:07:20Z)
• Parameter estimation with the steady states of non-Hermitian spin chains [0.0]
  We propose a scheme for parameter estimation with the steady states of non-Hermitian spin chains. The parameters to be estimated are encoded in the system via the external magnetic field that imposed on the first site of the chain.
  arXiv  Detail & Related papers  (2022-06-06T02:39:58Z)
• Rectification induced by geometry in two-dimensional quantum spin lattices [58.720142291102135]
  We address the role of geometrical asymmetry in the occurrence of spin rectification in two-dimensional quantum spin chains. We show that geometrical asymmetry, along with inhomogeneous magnetic fields, can induce spin current rectification even in the XX model.
  arXiv  Detail & Related papers  (2020-12-02T18:10:02Z)
• In and out of equilibrium quantum metrology with mean-field quantum criticality [68.8204255655161]
  We study the influence that collective transition phenomena have on quantum metrological protocols. The single spherical quantum spin (SQS) serves as stereotypical toy model that allows analytical insights on a mean-field level.
  arXiv  Detail & Related papers  (2020-01-09T19:20:42Z)

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.