Untwining multiple parameters at the exclusive zero-coincidence points with quantum control

• URL: http://arxiv.org/abs/2206.05999v2
• Date: Fri, 23 Dec 2022 02:52:03 GMT
• Title: Untwining multiple parameters at the exclusive zero-coincidence points with quantum control
• Authors: Yu Yang, Federico Belliardo, Vittorio Giovannetti and Fuli Li
• Abstract summary: A collection of parameters are said to be intertwined when their imprinting on a quantum probe is performed by a set of linearly dependent generators. We show that the parameters can be effectively untwined by inserting a sequence of balanced beam splitters. For the case of two time delays we prove that, when the employed probe is the frequency-correlated biphoton state, the untwining occurs in correspondence of exclusive zero-coincidence (EZC) point.
• Score: 3.600673741710729
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: In this paper we address a special case of "sloppy" quantum estimation procedures which happens in the presence of intertwined parameters. A collection of parameters are said to be intertwined when their imprinting on the quantum probe that mediates the estimation procedure, is performed by a set of linearly dependent generators. Under this circumstance the individual values of the parameters can not be recovered unless one tampers with the encoding process itself. An example is presented by studying the estimation of the relative time-delays that accumulate along two parallel optical transmission lines. In this case we show that the parameters can be effectively untwined by inserting a sequence of balanced beam splitters (and eventually adding an extra phase shift on one of the lines) that couples the two lines at regular intervals in a setup that remind us a generalized Hong-Ou-Mandel (GHOM) interferometer. For the case of two time delays we prove that, when the employed probe is the frequency-correlated biphoton state, the untwining occurs in correspondence of exclusive zero-coincidence (EZC) point. Furthermore we show the statistical independence of two time delays and the optimality of the quantum Fisher information at the EZC point. Finally we prove the compatibility of this scheme by checking the weak commutativity condition associated with the symmetric logarithmic derivative operators.

Related papers

• Evading noise in multiparameter quantum metrology with indefinite causal order [0.0]
  Quantum theory allows the traversing of multiple channels in a superposition of different orders. Various unknown parameters of the channels can be estimated by measuring only the control system. We demonstrate this capability for simultaneously estimating both unitary and noise parameters.
  arXiv  Detail & Related papers  (2023-09-13T18:00:02Z)
• Order-invariant two-photon quantum correlations in PT-symmetric interferometers [62.997667081978825]
  Multiphoton correlations in linear photonic quantum networks are governed by matrix permanents. We show that the overall multiphoton behavior of a network from its individual building blocks typically defies intuition. Our results underline new ways in which quantum correlations may be preserved in counterintuitive ways even in small-scale non-Hermitian networks.
  arXiv  Detail & Related papers  (2023-02-23T09:43:49Z)
• Joint quantum estimation of loss and nonlinearity in driven-dissipative Kerr resonators [0.0]
  We consider the realistic situation in which the parameters of interest are the loss rate and the nonlinear coupling, whereas the amplitude of the coherent driving is known and tunable. We also investigate the performance of quadrature detection, and show that for both parameters the Fisher information oscillates in time, repeatedly approaching the corresponding QFI.
  arXiv  Detail & Related papers  (2022-12-09T20:50:33Z)
• Singular Spectrum Analysis of Two Photon Interference from Distinct Quantum Emitters [0.0]
  Time trace of quantum interference pattern of two photons from two independent solid-state emitters is preprocessed by means of singular spectral analysis. This approach allows to single out the relevant oscillations from both the envelope and the noise, without resorting to fitting.
  arXiv  Detail & Related papers  (2022-12-01T22:04:05Z)
• Multiparameter quantum critical metrology [0.0]
  We argue that quantum criticality may also play a positive role in reducing the incompatibility in the simultaneous estimation of multiple parameters. The antiferromagnetic and ferromagnetic 1-D Ising chain with both transverse and longitudinal fields are analysed.
  arXiv  Detail & Related papers  (2022-03-23T19:00:01Z)
• Robust preparation of Wigner-negative states with optimized SNAP-displacement sequences [41.42601188771239]
  We create non-classical states of light in three-dimensional microwave cavities. These states are useful for quantum computation. We show that this way of creating non-classical states is robust to fluctuations of the system parameters.
  arXiv  Detail & Related papers  (2021-11-15T18:20:38Z)
• Generalized quantum circuit differentiation rules [23.87373187143897]
  Variational quantum algorithms that are used for quantum machine learning rely on the ability to automatically differentiate parametrized quantum circuits. Here, we propose the rules for differentiating quantum circuits (unitaries) with arbitrary generators.
  arXiv  Detail & Related papers  (2021-08-03T00:29:45Z)
• Accurate methods for the analysis of strong-drive effects in parametric gates [94.70553167084388]
  We show how to efficiently extract gate parameters using exact numerics and a perturbative analytical approach. We identify optimal regimes of operation for different types of gates including $i$SWAP, controlled-Z, and CNOT.
  arXiv  Detail & Related papers  (2021-07-06T02:02:54Z)
• Sequential Estimation of Convex Divergences using Reverse Submartingales and Exchangeable Filtrations [31.088836418378534]
  We present a unified technique for sequential estimation of convex divergences between distributions. The technical underpinnings of our approach lie in the observation that empirical convex divergences are (partially ordered) reverse submartingales. These techniques appear to be powerful additions to the existing literature on both confidence sequences and convex divergences.
  arXiv  Detail & Related papers  (2021-03-16T18:22:14Z)
• Time-Dependent Dephasing and Quantum Transport [68.8204255655161]
  We show that non-Markovian dephasing assisted transport manifests only in the non-symmetric configuration. We find similar results by considering a controllable and experimentally implementable system.
  arXiv  Detail & Related papers  (2021-02-20T22:44:08Z)
• Discrete Adjoints for Accurate Numerical Optimization with Application to Quantum Control [0.0]
  This paper considers the optimal control problem for realizing logical gates in a closed quantum system. The system is discretized with the Stormer-Verlet scheme, which is a symplectic partitioned Runge-Kutta method. A parameterization of the control functions based on B-splines with built-in carrier waves is also introduced.
  arXiv  Detail & Related papers  (2020-01-04T00:02:23Z)

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.