Abstract

The challenge to obtain pulsed superradiant regime in semiconductor structures stems from the fact that mode superradiance provides the highest possible rate of stimulated radiative transitions and gives rise to generation of ultrashort powerful pulses [1,2]. However, to achieve collective spontaneous recombination of free electrons and holes one has to overcome collisions that destroy the phased dipole oscillations of electron-hole pairs. The time T₂ of incoherent relaxation of polarization due to intraband scattering in semiconductors is as short as 0.1 ps, while the time of stimulated radiative transitions in direct band-gap materials used in standard heterolasers is typically 0.1 ns. As a result, collective effects in the radiative electron-hole recombination are suppressed.

© 2000 IEEE