Pikaruk O. Collective spontaneous recombination in quantum heterostructures and nanowires

Dicke' superradiance in single quantum well InGaAs/GaAs heterostructures and silicon nanowires is investigated. It is shown that full filling of the QW with the excited e-h pairs provides the form of PL spectrum, superradiance intensity and the relaxation time to be independent of pumping. This fact essentially distinguishes from superradiance in gases and solid. It is found that in highly strained quantum wells superradiance is observed also. However the smaller is deviation of the QW-layer thickness from the critical one the greater intensity and stability of superradiance. In samples with d-doping the relaxation time reaches its limit at smaller pumping. This fact is important for practical application. Investigation of silicon nanowires is shown that intensity of new infrared band related with complex structure of nanowires as well as the band width depend on exciting power likely to Dicke' superradiance. This gives rise to presume that these objects may be used as a basis for generator of ultrafast infrared pulses.