Development of high power quantum well lasers at RRCAT

TL;DR

This paper reports the development of high power quantum well laser diodes operating between 740 and 1000 nm, achieving over 5 Watts peak power, with detailed fabrication and testing procedures.

Contribution

It introduces a new high power quantum well laser diode design with specific fabrication techniques and performance results at RRCAT.

Findings

Achieved 5.3 W peak power at 853 nm

Developed laser diode arrays with 6-10 elements

Operated successfully in pulsed mode at room temperature

Abstract

We at RRCAT have recently developed high power laser diodes in the wavelength range of 740 to 1000 nm. A typical semiconductor laser structure is consisted of about 10 epilayers with different composition, thickness and doping values. For example, a laser diode operating at 0.8 micron has either GaAs or GaAsP quantum well as an active layer. The quantum well is sandwiched between AlGaAs wider bandgap waveguide and cladding layers. The complete laser structure is grown by metal organic vapour phase epitaxy technique and devices are fabricated through standard procedure using photolithography. We recently achieved about 5.3 Watt peak power at 853 nm. These laser diodes were tested under pulsed operation at room temperature for 500 nanosecond pulse duration with a duty cycle of 1:1000. Laser diode arrays consisting of 6-10 elements were also developed and tested for operation in pulsed mode at room temperature.