MICROGUN-PUMPED SEMICONDUCTOR-LASER

We demonstrate the feasibility of a novel microgun-pumped semiconductor laser. This is the most compact (a few cm3) and the lowest threshold electron-beam-pumped semiconductor laser ever reported. The electron source is provided by a 10(4)-10(5)/mm2 array of field emissive microtip cathodes each of 1.5 mum diam. The laser operates below 10 kV and below 1 A/cm2. Laser action in a quasi-cw mode with 5 mus pulses at 2 kHz has been obtained between 90 and 300 K with CdTe-CdMnTe graded index separate confinement quantum-well heterostructures, as well as with GaAs-GaAlAs structures. Since neither doping nor ohmic contacts are needed, the microgun laser can use all direct gap semiconductors. It appears as a viable solution for making compact II-VI lasers in the visible domain.