Nuclear magnetic resonance and nuclear spin relaxation in AlAs quantum well probed by ESR

Abstract

The study of nuclear magnetic resonance and nuclear spin-lattice relaxation was conducted in an asymmetrically doped to $n\sim 1.8\times 10^{11}$ cm${}^{-2}$ 16 nm AlAs quantum well grown in the $[001]$-direction. Dynamic polarization of nuclear spins due to the hyperfine interaction resulted in the so-called Overhauser shift of the two-dimensional conduction electron spin resonance. The maximum shifts achieved in the experiments are several orders of magnitude smaller than in GaAs-based heterostructures indicating that hyperfine interaction is weak. The nuclear spin-lattice relaxation time extracted from the decay of Overhauser shift over time turned out to depend on the filling factor of the two-dimensional electron system. This observation indicates that nuclear spin-lattice relaxation is mostly due to the interaction between electron and nuclear spins. Overhauser shift diminishes resonantly when the RF-radiation of certain frequencies was applied to the sample. This effect served as an indirect, yet powerful method for nuclear magnetic resonance detection: NMR quadrupole splitting of ${}^{75}$As nuclei was clearly resolved. Theoretical calculations performed describe well these experimental findings.

6 pages, 3 figures + supplemental material

References in corpus (6)

• Nuclear spin physics in quantum dots: an optical investigation
• Spin decoherence of a heavy hole coupled to nuclear spins in a quantum dot
• Valley splitting of AlAs two-dimensional electrons in a perpendicular magnetic field
• Stabilizing effect of nuclear quadrupole interaction on the polarization of electron-nuclear spin system in a quantum dot
• NMR profiling of quantum electron solids in high magnetic fields
• NMR Evidence for Spin Canting in a Bilayer nu = 2 Quantum Hall System

Cited by in corpus (2)

• Dynamic polarization of electron spins in indirect band gap (In,Al)As/AlAs quantum dots in weak magnetic field: experiment and theory
• Nuclear-induced dephasing and signatures of hyperfine effects in isotopically purified ${}^{13}$C graphene