Evidence for induced far‐infrared emission fromp‐Ge in crossed electric and magnetic fields

Experimental evidence is presented for stimulated far‐infrared emission from population‐inverted hot‐carrier system in p Ge. The spectroscopic study by use of an n‐InSb cyclotron‐resonance detector reveals that the spectrum of the emission consists of a fairly sharp band located at the photon energy ∼5 or ∼10 meV depending on the applied fields.