  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.
