Study On Fast-Slow Light Characteristics And Light Amplification In Cavity Magnomechanical System

In recent years,the strong coupling between spin ensembles and cavity photons has made remarkable progress,which promotes the emergence of cavity spintronics.Since the quantization of spin waves is highly robust to temperature,the strong coupling between light and matter at room temperature has been explored.This excellent characteristic makes the cavity magnomechanical system attract more and more attention.The ferromagnetic crystal yttrium iron garnet(YIG)plays an important role in the exploration of cavity magnomechanics.Moreover,its unique high spin density,low damping rate and high tunability are not possessed by the optomechanical system which has been studied extensively.Therefore,the cavity magnomechanical system is not only a good platform for the study of microscopic quantum information,but also can be used to explore macroscopic quantum phenomena.In recent years,with further research,many interesting phenomena have been obtained in the cavity magnetomechanical system,such as magnon blockade,phonon laser,bistable state,etc.Based on the cavity magnomechanical system,common macroscopic optical properties are investigated on the output spectrum,transmission spectrum and group delay curve of the system by using quantum optical correlation calculation.The specific research contents are as follows:Firstly,in the classical three-mode cavity magnomechanical system made up of the hybridization between microwave cavity and the YIG sphere,we explored magnon-induced transparency(MIT)phenomenon caused by the interaction between magnon and photon in microwave cavity,and magnomechnically-induced transparency(MMIT)phenomenon caused by the interaction between magnon and phonon when the magnetostrictive effect in the system was taken into account.Then we observed the change of the transparency effect of the system by adjusting the dissipation ratio between microwave cavity and magnon or the coupling intensity between microwave cavity and magnon,we also studied the variation of the fast-slow light effects with the dissipation ratio between microwave cavity and magnon.On the basis of the three-mode cavity magnomechanical system,an auxiliary microwave cavity was introduced to establish the four-mode hybrid cavity magnomechanical system.In this system,multi-transparency window was obtained in the absorption spectrum of the output field when the auxiliary cavity was set as dissipative cavity,light amplification was observed in the transmission spectrum of the output field when the auxiliary cavity was set as gain cavity.The effects of the interaction intensities and the detuning between photon and magnon in cavity 1 on the amplification effect of the system are investigated,then the intensity,position and region of light amplification are flexibly adjusted.Finally,the fast-slow light effect of the hybrid cavity magnomechanical system was analyzed,and the group delay of 3.5microseconds was achieved,which further explored variation of the group delay in the system when the gain or dissipation of the auxiliary cavity changed.The results show that the scheme can not only adjusted the transparency effect of the system,but also realize the ideal light amplification and conversion between fast-slow light by using the experimental parameters and reasonable parameter selection.