AbstractAn intense THz emission was observed from strained SiGe/Si quantum‐well structures under a strong pulsed electric field. The p‐type structures were MBE‐grown on n‐type Si substrates and δ‐doped with boron. Lines with wavelengths near 100 microns were observed in the emission spectrum. The modal structure in the spectrum gave evidence for the stimulated nature of the emission. The origin of the THz emission was attributed to intra‐center optical transitions between resonant and localized boron levels similar to that in compressed p‐Ge.