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arXiv · 1809.02881

Laplace transform approach for the dynamics of N qubits coupled to a resonator

Mirko Amico·Oleg L. Berman·Roman Ya. Kezerashvili
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Abstract

An approach to use the method of Laplace transform for the perturbative solution of the Schrödinger equation at any order of the perturbation for a system of $N$ qubits coupled to a cavity with $n$ photons is suggested. We investigate the dynamics of a system of $N$ superconducting qubits coupled to a common resonator with time-dependent coupling. To account for the contribution of the dynamical Lamb effect to the probability of excitation of the qubit, we consider counter-rotating terms in the qubit-photon interaction Hamiltonian. As an example, we illustrate the method for the case of two qubits coupled to a common cavity. The perturbative solutions for the probability of excitation of the qubit show excellent agreement with the numerical calculations.

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Mirko Amico, Oleg L. Berman, Roman Ya. Kezerashvili. 2018-09-18. Laplace transform approach for the dynamics of N qubits coupled to a resonator. https://doi.org/10.1016/j.physleta.2018.11.031

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