Abstract
We investigate the non-Gaussian feature of radiation in a circuit quantum electrodynamics(QED)system where two qubits are strongly coupled to a single-mode cavity.In the regime of ultrastrong coupling(USC),the rotating-wave approximation is not valid,and the Rabi Hamiltonian contains counter-rotating wave terms,leading to level crossing and avoided crossings in the energy spectrum.We further analyze the intensity-amplitude correlation of the output field in these two novel scenarios.In the USC regime,the creation and annihilation operators in the correlation function are replaced,allowing for the identification of non-Gaussian features in the output field.Our findings reveal that despite the absence of squeezing effects in the output light,significant non-Gaussian characteristics are present.Additionally,we demonstrate that as the driving or coupling strength increases,the non-Gaussian features of the output field become more pronounced.This suggests that USC systems hold broad potential applications in the realms of nonlinear optics and the generation of non-Gaussian states.
基金项目
National Natural Science Foundation of China(12104195)
Natural Science Foundation of Jiangxi Province of China(20232BAB211033)
NETL
NSTL
万方数据