Bloch oscillations in In-Ga-As-P/In-Ga-As-P heterostructures observed with time-resolved transmission spectroscopy

The coherent dynamics of Wannier-Stark (WS) states and localized states in In-Ga-As-P/In-Ga-As-P super-lattices is studied with time-resolved transmission experiments. The transmission of the probe is modulated due to the quantum interference of electronic Wannier-Stark states (Bloch oscillations) and the quantum interference of WS states and a growth-induced localized 2D state. Their frequency and decay provide information on the coherent coupling processes which is not accessible with linear optical techniques.