Resonant optical pumping of vertical-cavity semiconductor lasers

We investigate experimentally the threshold and slope efficiency of a vertical cavity surface-emitting semiconductor laser with halfwave spaced quantum wells as functions of the pump wavelength in the 700-900 nm. While most of these devices demonstrated to date have employed pump wavelengths in the range 700-760 nm for optimum absorption in the spacers between the quantum wells (and minimal absorption in the epitaxial mirror structure), we show that equally good performance be obtained using longer wavelengths appropriate for diode laser pumping, provided that the pump wavelength is chosen to match a resonant cavity mode. For maximum pumping efficiency using the latter technique a stabilized single-mode pump laser should be used.