Observation of magnetic field sweep direction dependent dynamic nuclear polarization under periodic optical electron spin pumping

被引：5

作者：

Macmahon, Michael ^{[1
]}

Iafrate, Joseph R. ^{[2
]}

Dominguez, Michael J. ^{[2
]}

Sih, Vanessa ^{[1
]}

机构：

[1] Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA

[2] Univ Michigan, Appl Phys Program, Ann Arbor, MI 48109 USA

来源：

PHYSICAL REVIEW B | 2019年 / 99卷 / 07期

基金：

美国国家科学基金会;

关键词：

RESONANCE; LOCKING;

D O I：

10.1103/PhysRevB.99.075201

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Optical pump-probe techniques are used to generate and measure electron spin polarization in a gallium arsenide epilayer in which the electron spin coherence time exceeds the mode-locked laser repetition period. Resonant spin amplification occurs at magnetic fields at which the electron spin polarization excited by successive laser pulses adds constructively. Measurements of Kerr rotation as a function of applied magnetic field and pump-probe time delay reveal nuclear spin polarization that aligns either with or against the external magnetic field depending on whether the applied magnetic field is being decreased or increased. Furthermore, the nuclear spin polarization magnitude varies in proportion to the perpendicular net electron spin polarization as the latter changes due to resonant spin amplification and other causes. We also report an experimental technique that reveals a minutes-long memory of precise field history in the electron-nuclear spin system.

引用

页数：10