Picosecond Modulation of the Fundamental Absorption of Light: Mapping of Oscillations and Depletion of Electron Population in the Field of Intrinsic Intense Stimulated Emission in an AlxGa1-xAs-GaAs-AlxGa1-xAs Heterostructure (Experimental Study)

A new, experimentally found phenomenon of quantum optics is described. In the beginning of high-power picosecond optical pumping of the GaAs layer in a heterostructure, intense picosecond stimulated emission is generated in this layer. The envelope of the fundamental absorption spectrum becomes modulated. This modulation cyclically changes with time, reflecting the radiation-excited deviation from the Fermi electron distribution, oscillating in time and energy space. The corresponding electron oscillations lead to the temporal modulation of emission. The investigation of this phenomenon revealed, along with other things, some fundamental processes, which should be explained in terms of the nonlinear optics of semiconductors; at the same time, they made it possible to explain some instabilities of the semiconductor laser radiation.