Electrical detection of spin accumulation and relaxation in p -type germanium

Large current modulation and tunneling magnetoresistance change by a side-gate electric field in a GaMnAs-based vertical spin metal-oxide-semiconductor field-effect transistor

“…The lateral spin MOSFETs, in which a current flows parallel to the substrate plane and is controlled by a gate electric field applied from the top of the channel, have a large current modulation capability (5 × 10 6 % 7 , 400% 8 and 10 7 % 9 ); however, the problem is the small MR ratio (0.1% 7 , 0.005% 8 and 0.027% 9 ). Meanwhile, epitaxial magnetic heterostructures were grown using various ferromagnets and semiconductors and some magnetotransport properties were studied 10 – 15 . Thus, a vertical spin field-effect transistor (FET), in which a current flows perpendicular to the film plane and is controlled by a gate voltage applied from the side surface of the channel, is promising for large MR.…”

“…The lateral spin MOSFETs, in which a current flows parallel to the substrate plane and is controlled by a gate electric field applied from the top of the channel, have a large current modulation capability (5×10 6 % 5 , 400% 6 and 10 7 % 7 ); however, the problem is the small MR ratio (0.1% 5 , 0.005% 6 and 0.027% 7 ). Meanwhile, a vertical spin field-effect transistor (FET) [8][9][10][11][12][13] , in which a current flows perpendicular to the film plane and is controlled by a gate voltage applied from the side surface of the channel, is promising for large MR. Previously, we reported ferromagnetic-semiconductor GaMnAs-based vertical spin FETs that exhibit large MR ratios (60% 14 and 5% 15 ).…”

Ordered structure of FeGe2 formed during solid-phase epitaxy

“…[15][16][17] Recently, the method of solid-phase epitaxy (SPE) of Ge was utilized in order to achieve a perfect crystallinity of the film and superior interface quality. [18][19][20] However, the diffusion of Fe and Si was not entirely prevented during the annealing process. Therefore, the Ge film contained some amount of Fe and Si, leading to a shift of the X-ray diffraction (XRD) peak of the Ge(Fe,Si) film and the formation of a superlatticelike structure inside the Ge(Fe,Si) film.…”

Nonmonotonic bias dependence of local spin accumulation signals in ferromagnet/semiconductor lateral spin-valve devices

“…On the other hand, the transport of spin-polarized charge currents flowing between two ferromagnets (FMs) through SCs also needs to be understood for SC spintronic applications [19][20][21][22][23][24]. To date, there have several reports on the electrical detection of the transport of spin-polarized charge carriers using local two-terminal spin-transport measurements in FM-SC-FM structures [25][26][27][28][29][30][31][32][33][34][35]. However, because only a few local spin signals have been discussed by a simultaneous comparison with nonlocal spin transport signals in SC-based LSV devices, some of the physics relevant to the magnitude of the local two-terminal spin signals is unclear [28-30, 33, 35-37].…”