Abstract

A tunable twin-guide laser diode (TTGLD) is one of the most attractive laser diodes, in terms of smooth wavelength tunability with wide tuning range.¹ The major problem with TTGLD’s is the simultaneous loss increase in the tuning layer associated with tuning current increase, which results in limited wavelength tunability. In this paper we demonstrate a novel TTGLD with a carrier-controlled tuning layer (InGaAsP SCH-MQW structure), where the refractive-index change and the loss increase are separately controlled. The increase in optical absorption loss associated with refractive-index change was suppressed by a factor of 3 compared with that for bulk-tuning-layer devices.

© 1993 Optical Society of America