Fig. 3: Device structures designed for spin amplification and the performance.
From: Topologically protected spin diffusion and spin generator using chalcogenide superlattices
a Three different devices were fabricated. Device-B had three spin injectors connected in parallel, Device-C had three or five spin-injectors connected in series, and Device-D was a control with a single injector. The electrode separation distance were fixed at 200 μm and the electrode width was 80 μm. b jc dependence of VISH signals of Device-B (blue), -C (red), and -D (gray), where jc was normalized per injector. The inset compares the signal voltage of Device-C (five electrodes) for electrode distances of 100 and 200 μm. c The VCISH hysteresis loop for Device-C (three electrodes) for jc = 1.0 mA. d A schematic showing spin accumulation μs in Device-B and -C. In Device-B, as jc flows in parallel through each interface, μs between the electrodes is weakened due to the opposite spin polarities. As a result, the outer μs is relatively weak. In Device-C, the jc direction of the central electrode is opposite to the outer electrode; thus, the same spins with ↑ or ↓ polarity are accumulated and this enhances μs between the electrodes. As a result, the js flows with a high intensity. B↑, SL, ⊙, and ⊗ indicate the magnetic field direction, SL, and jc directions, respectively. Dotted lines indicate boundaries between injector edges and SLs. Black curves and yellow arrows are μs polarity and js flow, respectively.
