Analysis of the transient response of nuclear spins in GaAs with/without nuclear magnetic resonance

Journal Article · Sun May 15 00:00:00 EDT 2016 · AIP Advances

DOI:https://doi.org/10.1063/1.4943610· OSTI ID:22611771

Rasly, Mahmoud; Lin, Zhichao; Yamamoto, Masafumi; Uemura, Tetsuya ^[1]

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1. Graduate School of Information Science and Technology, Hokkaido Univ., Sapporo 060-0814 (Japan)

As an alternative to studying the steady-state responses of nuclear spins in solid state systems, working within a transient-state framework can reveal interesting phenomena. The response of nuclear spins in GaAs to a changing magnetic field was analyzed based on the time evolution of nuclear spin temperature. Simulation results well reproduced our experimental results for the transient oblique Hanle signals observed in an all-electrical spin injection device. The analysis showed that the so called dynamic nuclear polarization can be treated as a cooling tool for the nuclear spins: It works as a provider to exchange spin angular momentum between polarized electron spins and nuclear spins through the hyperfine interaction, leading to an increase in the nuclear polarization. In addition, a time-delay of the nuclear spin temperature with a fast sweep of the external magnetic field produces a possible transient state for the nuclear spin polarization. On the other hand, the nuclear magnetic resonance acts as a heating tool for a nuclear spin system. This causes the nuclear spin temperature to jump to infinity: i.e., the average nuclear spins along with the nuclear field vanish at resonant fields of {sup 75}As, {sup 69}Ga and {sup 71}Ga, showing an interesting step-dip structure in the oblique Hanle signals. These analyses provide a quantitative understanding of nuclear spin dynamics in semiconductors for application in future computation processing.

• OSTI ID: 22611771
• Journal Information: AIP Advances, Vol. 6, Issue 5; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 2158-3226
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ARSENIC 75
CALCULATION METHODS
GALLIUM 69
GALLIUM 71
GALLIUM ARSENIDES
INJECTION
INTERACTIONS
MAGNETIC FIELDS
NUCLEAR MAGNETIC RESONANCE
POLARIZATION
SEMICONDUCTOR MATERIALS
SIMULATION
SOLIDS
SPIN
SPIN ORIENTATION
STEADY-STATE CONDITIONS
TIME DELAY