Manipulation of quantum phase transitions with Z 2 symmetry for a realistic hybrid system

Abstract

The critical behavior of the light-matter interactions in controllable systems provides an attractive direction for quantum manipulation. Inspired by “the broken symmetry will give rise to the quantum phase transitions (QPTs)”, the open-system QPTs of the Tavis–Cummings (TC) interactions with an extra second-order nonlinearity (SONL) are explored, where the systemic symmetry is reduced from U ( 1 ) to Z 2 . The critical behavior of a generic spins-microwave hybrid system is investigated using the standard mean-field approach in conjunction with different factors such as the SONL phase, the spins’ collective decay and dephasing, cavity dissipation, and detunings. The results show that all of the three decoherence factors and the detunings will affect its critical points, and the phase of SONL can especially exhibit a protective effect on QPTs. This study provides an encouraging example for mimicking the interesting light-matter interactions, and may further evoke some potential applications in quantum manipulations.

Keywords

• Hybrid system
• Quantum phase transition
• Tavis–Cummings model