孔型硅光子晶体中折叠式马赫-曾德尔干涉仪

本文首次设计了基于孔型硅光子晶体的折叠式马赫-曾德尔干涉仪。它由一个光反射器和几个光分束器构成。在干涉仪中，窄光束依赖自准直效应进行传输。利用时域有限差分法研究了折叠式马赫-曾德尔干涉仪的特性。结果表明，在0.255-0.270c/a的归一化频率范围内，干涉仪的两个透射谱均为正弦形且强度互补，透射谱的透射峰间距随着干涉仪两臂的光程差的增大而减小。该折叠式干涉仪结构紧凑，尺寸比非折叠式光子晶体马赫-曾德尔干涉仪要小许多。它有望作为信道解复用器应用于光子芯片中。

Folded Mach-Zehnder Interferometer in a Hole-type Silicon Photonic Crystal*

 A folded Mach-Zehnder interferometer in a hole-type silicon photonic crystal is proposed,which consists of one splitter and several mirrors.Light propagates between them employing self-collimation effect.Its performance is investigated based on finite-difference time-domain simulation technique.The two complementary transmission spectra at two output ports are both in the shape of sinusoidal curves in the frequency range from 0.255c/a to 0.270c/a.The peak spacing becomes smaller when the length difference between the two interfering branches is increased.This folded Mach-Zehnder interferometer with compact structure is much smaller than non-folded interference-type filters in photonic crystals.It may work as a wavelength division demultiplexer in high-density photonic integrated circuits.