High Power CW Operation of GaAs Injection Lasers at 77° K

Abstract

Continuous-wave operation of GaAs injection lasers depends critically upon the junction temperature <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> , <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> which, in turn, depends critically upon the heat flow from the laser body. <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> , <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sup> There are two instances in thel iterature in which continuous operation at 77° K was achieved at very low output power levels. In one, both mirror-ends of a Fabry-Perot structure were partly silvered; <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sup> in the other, stimulated emission was observed from a unit with four cleaved sides. <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> The purpose of this communication is to report that continuous-wave operation at 8400 Å of unsilvered GaAs lasers at 77° K has been consistently achieved at power levels near 0.65 watt and to describe the heat sink structure which has afforded the necessary thermal transfer characteristics