Optical polarization grating in semiconductors induced by exciton polaritons

A scattering-state approach is proposed to study the propagation of extreme ly short optical pulses through semiconductor heterostructures. The formali sm is applied to the propagation of exciton polaritons: Our simulated exper iments predict the formation of an exciton-induced polarization grating whe n the light pulse is resonant with the excitonic transition, and suggest pr oper physical conditions for its experimental detection. Moreover, our anal ysis of the polariton transport in thick semiconductor layers reveals a dec rease of the average polariton group velocity as a function of time, which we ascribe to a re-emission-reabsorption of light by excitons. [S0163-1829( 99)01043-7].