Exchange Scattering in Semiconductors: an Efficient Mechanism for the Orientation of Electron and Nuclear Spins

Exchange scattering of electrons by neutral donor impurities in semiconductors is examined. It is shown that the difference between the cross sections for different spin configurations is significant at realistic parameter values and can play an important role in the transport properties of semiconductor heterostructures. The possibility of using the exchange scattering mechanism to orient the spins of localized electrons and nuclei under optical pumping is discussed, which is of interest for both fundamental research and the development of spintronics.