Efficient spin transport along Si $⟨$100$⟩$ at room temperature

Abstract

We find efficient spin transport in Si at room temperature in lateral spin valves (LSVs). When the crystal orientation of the spin-transport channel in LSVs is changed from $⟨$110$⟩$, which is a conventional cleavage direction, to $⟨$100$⟩$, the maximum magnitude of the spin signals is markedly enhanced. From the analyses based on the one-dimensional spin diffusion model, we can understand that the spin injection/detection efficiency in Si$⟨$100$⟩$ LSVs is larger than that in Si$⟨$110$⟩$ ones. We infer that, in Si-based LSVs, the spin detection efficiency of the pure spin current is related to the crystallographic orientation of the valley structures of the conduction band in Si.

4 pages, 3 figures