标题： Hall检测的ppm自旋极化 显示英文标题

标题： Hall detection of a ppm spin polarization

摘要： 霍尔效应已被用作磁场所和磁化的敏感探测器。 在自旋电子学中，奇特的现象通常源于非平衡自旋极化或磁化，这很难直接测量。 挑战在于总磁矩非常小，超出了超导量子干涉装置和振动样品磁强计或诸如X射线磁圆二色光谱等光谱方法的检测范围。 克尔效应仅在直接带隙半导体中足够灵敏，在这些半导体中，克尔角可以被共振增强。 在这里，我们证明即使在一百万个原子中只有一个多余的自旋，也可以在室温下通过霍尔效应进行检测。 这种新型霍尔效应不由自旋霍尔电导率所控制，而是由其能量导数所控制，因此与自旋能斯特效应有关。 显示英文摘要

摘要： Hall effects have been employed as sensitive detectors of magnetic fields and magnetizations. In spintronics, exotic phenomena often emerge from a non-equilibrium spin polarization or magnetization, that is very difficult to measure directly. The challenge is due to the tiny total moment, which is out of reach of superconducting quantum interference devices and vibrating sample magnetometers or spectroscopic methods such as X-ray magnetic circular dichroism. The Kerr effect is sufficiently sensitive only in direct gap semiconductors, in which the Kerr angle can be resonantly enhanced. Here we demonstrate that even one excess spin in a million can be detected by a Hall effect at room temperature. The novel Hall effect is not governed by the spin Hall conductivity but by its energy derivative thereby related to the spin Nernst effect.