Electroabsorptive Fabry-Perot reflection modulators with asymmetric mirrors

Abstract

A normally-on electroabsorptive surface-normal Fabry-Perot reflection modulator is reported with an on/off ratio of 22, insertion loss of 3.7 dB, and bandwidth of 3.4 nm for an operating voltage swing of 11 V. The asymmetric Fabry-Perot structure is made with asymmetric mirrors using a quarter-wavelength grating of 15 1/2-periods on the bottom and an air-semiconductor interface on the top. The active region is 1.4 mu m thick and composed of 100AA GaAs/100 A Al/sub 0.2/Ga/sub 0.8/As multiple quantum wells. The structure provides both high-efficiency and bandwidth for surface-normal modulators.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>