C-SPIN IRG2, Oklahoma/Arkansas, DMR-0520550

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.

Electron Spin Effects in Narrow Gap Semiconductors

(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).

(a)

62.4 62.7 63.0

4.28

Rxx

(k)

f (MHz)

4.27

115In(b)