非线性光子晶体中光敏超棱镜现象的研究

The light intensity-dependent superprism phenomenon in nonlinear photonic crystals

基于非线性时域有限差分法,模拟了克尔非线性光子晶体中的光敏超棱镜现象.结果发现,当光强变化230W/μm时,两束光在空间上能被分开10°,选取较大的基本功率将有助于提高其光强分辨率.而且,当自抽运光较强时,光子晶体中光波的波矢方向将会发生转动.此外,光束在非线性光子晶体中长距离传播时,透过率的变化将经历几个不同的阶段,分别对应于不同原因所造成的光强损耗.

We investigate the light intensity-dependent superprism phenomenon in the two-dimensional Kerr nonlinear photonic crystal （PhC） by nonlinear finite-difference time-domain （FDTD） technique. Results show that when the intensity of the self-pumping beam is increased from 70 to 300 W/μm, the refraction angle of the beam can be tuned about 10 degree. Furthermore, when the input power is high enough, the wave vector can be rotated by the local refractive index interfaces induced by the pumping power. By monitoring the transmission efficiency at different depths in PhCs, the propagating beam is found to undergo several states which correspond to different power loss mechanisms.