arXiv subjects

Taiki Nishijima

Publications and source records attributed to Taiki Nishijima.

2 recordsLinked to original sources

arXiv2024

Circular photogalvanic effect in an inversion-symmetry-broken bilayer germanium nanosheet

Spin-to-charge conversion in monolayer and bilayer germanium(Ge) nanosheets was demonstrated via the circular photogalvanic effect (CPGE). The CPGE current generated in a spin-splitting state of the Ge nanosheet reached a maximum value when the thickness of the Ge nanosheet corresponded to bilayer germanene, indicating that the top layer of the bilayer Ge nanosheet mainly contributed to the spin-to-charge conversion. Because the hybridization of orbitals is suppressed by isolation from the bottom Al layer for the top Ge nanosheet, the observed spin-to-charge conversion has a possibility to be related to the intrinsic features of germanene with breaking of inversion symmetry.

cond-mat.mtrl-sci↗

arXiv2020

Optical visualization of the enhanced spin Hall effect in bismuth doped silicon

Direct visualizations of spin accumulation due to the enhanced spin Hall effect (SHE) in bismuth (Bi) - doped silicon (Si) at room temperature are realized by using helicity-dependent photovoltage (HDP) measurements. Under application of a dc current to the Bi-doped Si, clear helicity-dependent photovoltages are detected at the edges of the Si channel, indicating a perpendicular spin accumulation due to the SHE. In contrast, the HDP signals are negligibly small for phosphorus-doped Si. Compared to a platinum channel, which has a large spin Hall angle, more than two-orders of magnitude larger HDP signals are obtained in the Bi-doped Si.

cond-mat.mtrl-sci↗