Scanning thermal microscopy of a vertical-cavity surface-emitting laser

A scanning thermal microscope was used to measure the temperature distribution inside a vertical-cavity surface-emitting laser. The peak temperature occurred at the intersection of the optical axis and the active quantum wells, and increased with input power at a rate of 0.74 degrees C/mW. Comparison with model predictions showed that the n mirrors and the substrate produce higher heat generation rates, possibly due to Joule heating and/or the absorption of spontaneous emissions that are often neglected in models. (C) 1997 American Institute of Physics.