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 104–105/mm2 array of field emissive microtip cathodes each of 1.5 μm diam. The laser operates below 10 kV and below 1 A/cm2. Laser action in a quasi‐cw mode with 5 μs 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.