Broadening of the longitudinal modes due to transient heating in optically pumped semiconductor lasers

Abstract
We have found that the output spectra of cleaved GaAs lasers are broadened when they are optically pumped with a high-energy pulsed laser. We believe the effect is due to transient heating. A one-dimensional heat-flow equation is solved and the results predict the observed broadening. Ways of improving the mode spectra by reducing the broadening are discussed.