A NOVEL ALL-OPTICAL BISTABLE DEVICE IN A NONINTERFEROMETRIC DOUBLE P-I(ESQWS)-N DIODE STRUCTURE

A novel all-optical bistable double p-i-n structure (p-i-n-i-p) is dem onstrated. Two thin intrinsic regions made of extremely shallow quantu m wells (ESQW's) allow both large electric field modulation and strong light absorption, enhancing the optical bistability. Due to the nonin terferometric nature, the double p-i(ESQW's)-n structure is not sensit ive to thickness fluctuation, unlike the previously reported all-optic al bistable device of asymmetric Fabry-Perot cavity structure, Uniform and high performance is realized with a contrast ratio of similar to 2.1, a reflectivity change of similar to 24%, and a bistable loop widt h of similar to 75% at 1 mW optical power without external bias.