Tsutomu MUNAKATA, Yasumasa KASHIMA and Akio MATOBA

Optical Device Division, Oki Electric Industry Co., Ltd., Higashiasakawa, Hachioji, Tokyo, 193 Japan

(Received June 26, 1996; Accepted September 12, 1996)

An optical output power exceeding 210 mW has been achieved using 1.625-μm strained multiple quantum well lasers at a forward current of 800 mA under pulsed operation. We introduced tensile-strained barrier layers to increase internal quantum efficiency. High quantum efficiency is attributed to improved of hole injection efficiency and suppressed electron overflow from wells. The 1.625-μm high-power lasers are expected to be applied to optical time-domain reflectometers, which enable regular communication light to be used.

Key words : high-power strained multiple quantum well laser, 1.625 μm, optical-time domain reflectometer, tensile strain in barrier layers, carrier injection