CONDUCTION-BAND SPIN SPLITTING AND NEGATIVE MAGNETORESISTANCE IN A(3)B(5) HETEROSTRUCTURES

The quantum interference corrections Io the conductivity are calculate d for an electron gas in asymmetric quantum wells in a magnetic field, The theory takes into account two different types of the spin splitti ng of the conduction band: the Dresselhaus terms, both linear and cubi c ill the wave vector, and the Rashba term, linear in the wavevector. While the contributions of all terms of the conduction band splitting into the D'yakonov-Perel' spin relaxation rate are additive, in the co nductivity the two linear terms cancel each other. The theory agrees v ery well with experimental results and enables one to determine experi mentally parameters of the spin-orbit splitting of the conduction band .