Quantum criticality in a generalized Dicke model
نویسندگان
چکیده
We employ a generalized Dicke model to study theoretically the quantum criticality of an extended two-level atomic ensemble interacting with a single-mode quantized light field. Effective Hamiltonians are derived and digonalized to investigate numerically their eigenfrequencies for different quantum phases in the system. Based on the analysis of the eigenfrequencies, an intriguing quantum phase transition from a normal phase to a super-radiant phase is revealed clearly, which is quite different from that observed with a standard Dicke model.
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تاریخ انتشار 2006