Hamiltonian and Lindbladian Parameter Estimation

ORAL

Abstract

Estimating the parameters governing the dynamics of a system is a prerequisite for its control. We present a simple but powerful new method to estimate the Hamiltonian (or Lindbladian) governing a quantum system of a few qubits. Our method makes efficient use of all measurements taken of the system and it saturates the information-theoretic limits for such an estimator. Importantly, it is inherently robust to state preparation and measurement errors. It is not limited to evaluating only a fixed set of possible gates, rather it estimates the complete Hamiltonian of the system. The estimator is applicable to any Hamiltonian that can be written as a piecewise-differentiable function and it can easily include estimators for the non-unitary parameters as well. At the heart of our approach is a stochastic gradient descent over the difference between experimental measurement and model prediction.

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Presenters

  • Stefan Krastanov

    Departments of Physics and Applied Physics, Yale University

Authors

  • Stefan Krastanov

    Departments of Physics and Applied Physics, Yale University

  • Sisi Zhou

    Departments of Physics and Applied Physics, Yale University

  • Steven Flammia

    Univ of Sydney, School of Physics, University of Sydney, Unversity of Sydney, Yale University, Quantum Benchmark, University of Sydney; Yale University; Quantum Benchmark Inc.

  • Liang Jiang

    Yale Univ, Applied Physics, Yale University, Departments of Physics and Applied Physics, Yale University, Departments of Applied Physics and Physics, Yale Univ, Department of Applied Physics and Physics, Yale University