Spin polarization gate device based on the chirality-induced spin selectivity and robust nonlocal spin polarization

Abstract

Nonlocal spin polarization phenomena are thoroughly investigated in the devices made of chiral metallic single crystals of CrNb${}_3$S${}_6$ and NbSi${}_2$ as well as of polycrystalline NbSi${}_2$. We demonstrate that simultaneous injection of charge currents in the opposite ends of the device with the nonlocal setup induces the switching behavior of spin polarization in a controllable manner. Such a nonlocal spin polarization appears regardless of the difference in the materials and device dimensions, implying that the current injection in the nonlocal configuration splits spin-dependent chemical potentials throughout the chiral crystal even though the current is injected into only a part of the crystal. We show that the proposed model of the spin dependent chemical potentials explains the experimental data successfully. The nonlocal double-injection device may offer significant potential to control the spin polarization to large areas because of the nature of long-range nonlocal spin polarization in chiral materials.

8 pages, 8 figures

References in corpus (4)

• Direct electronic measurement of the spin Hall effect
• Observation of inverse spin Hall effect in bismuth selenide
• Electrical detection of the spin polarization due to charge flow in the surface state of the topological insulator Bi_1.5 Sb_0.5 Te_1.7 Se_1.3
• Detection of chirality-induced spin polarization over millimeters in polycrystalline bulk samples of chiral disilicides NbSi${}_2$ and TaSi${}_2$