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arXiv · 1911.00138

Dynamics of a qubit-oscillator system with periodically varying coupling

Mirko Amico·Roman Ya. Kezerashvili
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Abstract

The dynamics of qubits coupled to a harmonic oscillator with time-periodic coupling is investigated in the framework of Floquet theory. This system can be used to model nonadiabatic phenomena that require a periodic modulation of the qubit/oscillator coupling. The case of a single qubit coupled to a resonator populated with $n= 0,1$ photons is explicitly treated. The time-dependent Schrödinger equation describing the system's dynamics is solved within the Floquet formalism and a perturbative approach in the time- and Laplace-domain. Good quantitative agreement is found between the analytical and numerical calculations within the Floquet approach, making it the most promising candidate for the study of time-periodic problems. Nonetheless, the time- or Laplace-domain perturbative approaches can be used in the presence of aperiodic time-dependent terms in the Hamiltonian.

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Mirko Amico, Roman Ya. Kezerashvili. 2019-10-31. Dynamics of a qubit-oscillator system with periodically varying coupling. https://doi.org/10.1088/1361-6455%2Fabc7fc

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