Theoretical Study of Enhanced Steady-State Spin Squeezing
Spin squeezed states are important quantum resources for achieving high-precision quantum precise measurement and quantum information processing.How to achieve steady-state squeezing of atomic spin is one of the frontier topics in this research field.Currently,the realization methods of steady-state spin squeezing mainly rely on the special dissipation of atomic systems.In this study,we find that the degree of steady-state squeezing produced by pure dissipative systems is very low in certain parameter ranges.In order to solve this problem,this paper proposes a new scheme to further improve the spin squeezing degree of quantum systems by adding a one-axis twisting nonlinear evolution to the dissipative system,and finds that the increase of the spin squeezing degree is limited to 3 dB.It is also found that even in the presence of noise,the increase in the squeezing degree of the system due to the evolution of one-axis twisting can still reach 3 dB,which proves that this scheme has strong robustness against noise.