The electrical turn-on characteristics of vertical-cavity surface-emitting lasers

We present a detailed comparison of the electrical turn-on characteristics of 980 nm vertical-cavity surface-emitting lasers ~VCSELs! with simulations using a recently extended laser simulator. It is shown that the three recombination mechanisms, spontaneous emission, Shockley–Read–Hall recombination, and Auger recombination, result in distinctly different exponential current–voltage dependencies below threshold. Therefore, information can be extracted about the relative strength of the recombination rates due to those processes, and their relative contributions to the threshold current can be assessed. We show that for the VCSELs studied in this work, spontaneous emission is the dominant contribution to the threshold current. © 2003 American Institute of Physics. @DOI: 10.1063/1.1628816#