Presentation Information
[7a-N302-9]Two-stage Formation of an Anomalously Large Nuclear Field in Bulk n-AlGaAs
〇Andong Shen1, Reina Kaji1, Sota Yamamoto2, Tetsuya Uemura3, Satoru Adachi1 (1.Eng, Hokkaido Univ., 2.Eng, Tohoku Univ., 3.IST, Hokkaido Univ.)
Keywords:
Nuclear spin polarization,AlGaAs
This study found that an unusually large nuclear magnetic field (BN) of up to 1.1 T can be slowly generated under an oblique magnetic field in n-AlGaAs, exhibiting a two-stage formation process. Time-resolved Kerr rotation (TRKR) measurements, and "pre-pump" and "dark-time" sequences were used to observe the formation and relaxation dynamics of BN.
The conventional model for nuclear spin polarization (NSP) fails to explain the observed two-stage formation. To address this, a modified model was proposed that divides nuclear spins into two groups: those near electron localization sites (ILoc) and those in the surrounding region (ISur). This new model successfully reproduces the experimental two-stage formation dynamics. The study aims to reveal the underlying mechanisms, considering electron localization, nuclear quadrupole interactions, and spin diffusion, to explain the origin of these large nuclear fields.
The conventional model for nuclear spin polarization (NSP) fails to explain the observed two-stage formation. To address this, a modified model was proposed that divides nuclear spins into two groups: those near electron localization sites (ILoc) and those in the surrounding region (ISur). This new model successfully reproduces the experimental two-stage formation dynamics. The study aims to reveal the underlying mechanisms, considering electron localization, nuclear quadrupole interactions, and spin diffusion, to explain the origin of these large nuclear fields.