本文通过建立(?)形四能级原子系统,研究了微波驱动精细结构能级跃迁引起的电磁诱导负折射效应.微波场作用于基态精细结构能级之间,与不同精细结构能级之间的电偶极矩或磁偶极矩发生耦合,使系统在某些频率处呈现负折射特性.同时,两个耦合场各自激励一对基态和激发态之间的光学跃迁.通过改变两个耦合场的频率失谐量控制负折射区域的频带宽度.结果表明,耦合场失谐时出现负折射特性的频率范围比耦合场共振时迅速缩小,而且耦合场负失谐和正失谐时的变化规律不同.
Electromagnetically induced negative refraction induced by microwave field driving hyperfine level transition is studied by proposing a quasi-lambda type four-level system.Negative refraction characteristics are observed when hyperfine levels within ground state are driven by a microwave field which interacts with electric dipole moment or magnetic dipole moment at different hyperfine levels.In addition,two optical transitions between ground state and excited state are driven by two coupling fields respectively,and the frequency bandwidth of negative refraction is controlled by the detuning of two coupling fields.It is shown that frequency bandwidth of negative refraction is much narrower under off-resonant coupling field than under the resonant coupling field and there is a significant difference in behavior between positively detuned coupling field and negatively detuned coupling field.