薄膜介质内慢光现象及其理论研究

Slow Light Phenomenon and Its Theory in Thin Film Media

针对薄膜介质内的慢光现象,研究了它的产生机理及影响因素。由于薄膜介质的厚度很小,因此假设磁场沿厚度方向的分量与厚度无关,从而得到薄膜介质中光传播的色散关系,推导出光在薄膜中传播的群速度表达式。深入分析了光的频率、薄膜介质的折射率以及薄膜介质的厚度对群速度的影响,得到了这些影响因素对光在薄膜介质中群速度的影响曲线。研究表明选取适当的光频率、薄膜折射率和薄膜厚度可以大幅度地降低光在薄膜介质中的传播速度,为薄膜介质中的慢光技术提供了理论依据。

Aiming at slow light phenomenon in the thin film, the mechanism of slow light and its influence factors are investigated. Because the thickness of the thin film is extremely small, an assumption that the component of the magnetic field in the thickness direction is independent of the thickness is proposed. Then the dispersion relation in the thin film media is obtained. The expression of the group velocity of the light in the thin film media is deduced. Then the influences of the frequency of the light, the refractive index of the thin film media and the thickness of the thin film media on the group velocity are analyzed. The influence curves of the group velocity in the thin film media are acquired. The research shows that speed of the light in the thin film media can be greatly reduced by selecting the appropriate influence factors. It provides a theoretical basis for the slow light technology in thin film media.