负折射原子介质中的克尔非线性增强

分析了四能级原子系统中左手材料的克尔非线性特性。研究表明，由于量子干涉作用,选择合适的物理参数，可以在这种负折射原子介质中获得无吸收增强的克尔非线性。这种介质不但表现出很强的克尔非线性而且还可以起到相位补偿和振幅补偿的作用。

The Kerr nonlinearity of a left-handed material is analyzed in a four-level atomic system. It is shown that, due to the effect of quantum interference, a large enhanced Kerr nonlinearity accompanied by vanishing absorption can be realized via choosing appropriate parameters in this negative refraction atomic medium. It not only shows the large nonlinearity but also acts as the phase and amplitude compensating effects.