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Macroscopic Quantum Criticality in a Circuit QED

Y. D. Wang·H. T. Quan·Yu-xi Liu·C. P. Sun·Franco Nori
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Abstract

Cavity quantum electrodynamic (QED) is studied for two strongly-coupled charge qubits interacting with a single-mode quantized field, which is provided by a on-chip transmission line resonator. We analyze the dressed state structure of this superconducting circuit QED system and the selection rules of electromagnetic-induced transitions between any two of these dressed states. Its macroscopic quantum criticality, in the form of ground state level crossing, is also analyzed, resulting from competition between the Ising-type inter-qubit coupling and the controllable on-site potentials.

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Y. D. Wang, H. T. Quan, Yu-xi Liu, C. P. Sun, Franco Nori. 2006-01-04. Macroscopic Quantum Criticality in a Circuit QED. https://arxiv.org/abs/quant-ph/0601026

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