RESONANT OPTICAL-PUMPING OF VERTICAL-CAVITY SURFACE-EMITTING LASERS

We experimentally investigate the threshold and slope efficiency of a vertical cavity surface-emitting laser (VCSEL) as functions of the pum p wavelength in the 700-900 nm range. While most VCSELs exploit pump w avelengths in the 700-760 nm range for optimum absorption in the space rs between the quantum wells, we show that equally good performance ca n be obtained using longer wavelengths appropriate for diode laser pum ping, provided that the pump wavelength is chosen to match a cavity re sonance.