Nuclear spin relaxation in n-GaAs: from insulating to metallic regime

Abstract

Nuclear spin relaxation is studied in n-GaAs thick layers and microcavity samples with different electron densities. We reveal that both in metallic samples where electrons are free and mobile, and in insulating samples, where electrons are localized, nuclear spin relaxation is strongly enhanced at low magnetic field. The origin of this effect could reside in the quadrupole interaction between nuclei and fluctuating electron charges, that has been proposed to drive nuclear spin dynamics at low magnetic fields in the insulating samples. The characteristic values of these magnetic fields are given by dipole-dipole interaction between nuclei in bulk samples, and are greatly enhanced in microcavities, presumably due to additional strain, inherent to micro and nanostructures.

11 pages, 4 figures

References in corpus (5)

• Nuclear spin physics in quantum dots: an optical investigation
• Spin relaxation of localized electrons in n-type semiconductors
• Demagnetization of Quantum Dot Nuclear Spins: Breakdown of the Nuclear Spin Temperature Approach
• Light-induced nuclear quadrupolar relaxation in semiconductors
• Ultimate photo-induced Kerr rotation achieved in semiconductor microcavities

Cited by in corpus (8)

• Spin temperature concept verified by optical magnetometry of nuclear spins
• Nuclear spin diffusion in the central spin system of a GaAs/AlGaAs quantum dot
• Simultaneous measurements of nuclear spin heat capacity, temperature and relaxation in GaAs microstructures
• Unveiling the electron-nuclear spin dynamics in an n-doped InGaAs epilayer by spin noise spectroscopy
• Nuclear spin cooling by helicity-alternated optical pumping at weak magnetic fields in $n$-GaAs
• High-efficiency optical pumping of nuclear polarization in a GaAs quantum well
• Slowly generated anomalously large nuclear field in bulk n-AlGaAs
• Nuclear spin polaron-formation: anisotropy effects and quantum phase transition