Study And Application Of Optical Transmission Effect In The Coupled System Of Microcavity Photon-phonon/magnon

Combined with mechanical harmonic oscillator or magnon degrees of freedom of cavity for the realization of the optomechanical/magnonic effect of information transmission and processing provides a unique platform,and a close relationship has been established between nanophotonics and nanomechanics or magnetics.In recent years,the cavity optomechanical system and cavity magnonics system are the hot topics of people's research.The researches based on the nonlinear interactions in the cavity optomechanical system and cavity magnonics system,including optomechanical interaction,magnetostrictive effect and magnon Kerr effect,cause a lot of interesting phenomena,such as optomechanically induced transparency,quantum entanglement,photon blockade,phonon laser,bistability etc.In this paper,we mainly study the effect of light transmission based on the nonlinear interaction in the cavity optomechanical system and cavity magnonics system,including high-order sideband generation in the cavity optomechanical system,and slow light and nonreciprocity in the cavity magnonics system.The main content can be divided into three parts:First,we respectively study high-order sideband generation in different cavity optomechanical systems.First of all,high-order sideband generation in an optomechanical system coupled to a charged object is discussed,and the results show that the Coulomb-interaction-dependent effect of high-order sideband generation exhibits essential difference between the cases of weak and strong control fields,and it is found that only under the condition of strong control field,can the sensitive Coulombinteraction-dependent effect of high-order sideband generation be generated and the charge number can be accurately measured.Then,in a two-cavity optomechanical system with periodically modulated photon hopping,we find the high-order sideband generation can be induced originating from the parametric frequency conversion process and the nonlinear optomechanical interactions process.Both the modulation amplitude and frequency of photon hopping between the two cavities have flexible manipulation on the high-order sideband generation at the low pump power level.Selective generation of particular sideband spectrum may also been achieved when the parametric conversion process is dominant.Finally,these results may provide further insights into the understanding of the high-order sideband generation,and find applications in optical frequency converters and optical frequency combs.Second,we show a tunable slow light in a cavity magnomechanical system consisting of photon,magnon and phonon modes with a nonlinear phonon-magnon interaction,which originates from magnetostrictive forces.For a strong photon-magnon coupling strength,it can be observed a transparency(absorption)window for the probe field by placing a strong control field on the red(blue)detuned sideband of the hybridized modes,which are comprised of photons and magnons.In this work,we mainly show the characteristic changes in dispersion in the range of the transparency window.The value of group delay can be continuously adjusted by using different frequencies of magnon,which are determined by the external bias magnetic field and therefore can be conveniently tuned in a broad range.Both the intensity and the frequency of the control field have an influence on the slow light,and one may achieve long-lived slow light(group delay of millisecond order)by enlarging the pump power.These results may find applications in information interconversion based on coherent coupling among photons,phonons and magnons.Third,we propose to realize the nonreciprocal transmission of a microwave field in a two-cavity magnonics system consisting of two microwave cavities and a yttrium iron garnet(YIG)sphere,which is placed in one of them.It is discovered that magnon Kerr nonlinearity effect leads to the occurrence of magnon bistability and different magnonic responses for the forward and backward propagation of the microwave field.The different magnonic responses play a crucial role in the nonreciprocal transmission,which essentially breaks the space-reversal symmetry of transmission of the microwave field.More importantly,by adjusting the external bias magnetic field,which determines the frequency of the magnon,we can obtain a variable isolation of the microwave field or even its transmission in only one direction,which may be utilized to achieve light diodes.In addition,by increasing the strength of a microwave source applied to drive the magnon mode,stronger nonreciprocal transmission can be observed.These results may open a route to exploiting various nonreciprocal effects in cavity magnonics systems.