1. C-SPIN IRG2, Oklahoma/Arkansas, DMR-0520550 (a) (b) Electron Spin Effects in Narrow Gap Semiconductors Semiconductors with narrow energy gaps have properties that can be advantageous for devices that exploit electron spin. Electrons in InSb have a spin lifetime that is sufficiently long for the spin to be manipulated and/or detected. Coupling between electron spins and nuclear spins in InSb quantum wells was studied in quantum Hall ferromagnets (QHF) with domain structures. Dynamic nuclear polarization via the hyperfine interaction occurs when a large current flows through the QHF. Resistively-detected nuclear magnetic resonance (RDNMR) signals of both In and Sb are prominent. (a) Electron spin relaxation rates in InSb as a function of electron kinetic energy. The purple (blue-green) lines indicate theoretical limits for the Elliot-Yafet (Dyakanov-Perel) process. (b) Quadrupole splittings of 115In measured by the RDNMR technique applied to an InSb quantum well. The gray line is a fit with nine Gaussian curves (black line).