Laboratoire Charles Coulomb UMR 5221 CNRS/UM2, Université Montpellier 2, Place Eugene Bataillon, 34296 Montpellier Cedex 05, France.
Phys Rev Lett. 2013 Aug 23;111(8):087603. doi: 10.1103/PhysRevLett.111.087603. Epub 2013 Aug 20.
We report on the nondestructive measurement of nuclear magnetization in n-GaAs via cavity enhanced Faraday rotation. In contrast with the existing optical methods, this detection scheme does not require the presence of detrimental out-of-equilibrium electrons. Specific mechanisms of the Faraday rotation are identified for (i) nuclear spins situated within the localized electron orbits, these spins are characterized by fast dynamics, (ii) all other nuclear spins in the sample characterized by much slower dynamics. Our results suggest that even in degenerate semiconductors nuclear spin relaxation is limited by the presence of localized electron states and spin diffusion, rather than by Korringa mechanism.
我们通过腔增强法拉第旋转报告了在 n-GaAs 中对核磁化强度的非破坏性测量。与现有的光学方法不同，这种探测方案不需要存在有害的非平衡电子。对于（i）位于局域电子轨道内的核自旋，以及（ii）样品中所有其他具有较慢动力学的核自旋，我们确定了法拉第旋转的具体机制。我们的结果表明，即使在简并半导体中，核自旋弛豫也受到局域电子态和自旋扩散的限制，而不是科里根机制。
