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arXiv · 1704.00486

Measurement of the topological Chern number by continuous probing of a qubit subject to a slowly varying Hamiltonian

Peng Xu·Alexander Holm Kiilerich·Ralf Blattmann·Yang Yu·Shi-Liang Zhu·Klaus Mølmer
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Abstract

We analyze a measurement scheme that allows determination of the Berry curvature and the topological Chern number of a Hamiltonian with parameters exploring a two-dimensional closed manifold. Our method uses continuous monitoring of the gradient of the Hamiltonian with respect to one parameter during a quasi-adiabatic quench of the other. Measurement back-action leads to disturbance of the system dynamics, but we show that this can be compensated by a feedback Hamiltonian. As an example, we analyze the implementation with a superconducting qubit subject to time varying, near resonant microwave fields; equivalent to a spin 1/2 particle in a magnetic field.

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Peng Xu, Alexander Holm Kiilerich, Ralf Blattmann, Yang Yu, Shi-Liang Zhu, Klaus Mølmer. 2017-07-07. Measurement of the topological Chern number by continuous probing of a qubit subject to a slowly varying Hamiltonian. https://doi.org/10.1103/physreva.96.010101

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