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arXiv · 1204.0953

Unified analytical treatments to qubit-oscillator systems

Shu He·Yu-Yu Zhang·Qing-Hu Chen·Xue-Zao Ren·Tao Liu·Ke-Lin Wang
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Abstract

An effective scheme within two displaced bosonic operators with equal positive and negative displacements is extended to study qubit-oscillator systems analytically in an unified way. Many previous analytical treatments, such as generalized rotating-wave approximation (GRWA) [Phys. Rev. Lett. 99, 173601 (2007)] and an expansion in the qubit tunneling matrix element in the deep strong coupling regime [Phys. Rev. Lett. 105, 263603 (2010)] can be recovered straightforwardly in the present scheme. Moreover, further improving GRWA and extension to the finite-bias case are implemented easily. The analytical expressions are then derived explicitly and uniquely, which work well in a wide range of the coupling strengthes, detunings, and static bias including the recent experimentally accessible parameters.

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Shu He, Yu-Yu Zhang, Qing-Hu Chen, Xue-Zao Ren, Tao Liu, Ke-Lin Wang. 2012-04-04. Unified analytical treatments to qubit-oscillator systems. https://doi.org/10.1088/1674-1056/22/6/064205

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