14:15 〜 14:30
▲ [21p-W241-5] Spin transport in a two-dimensional electron gas in an AlGaAs/GaAs structure at room temperature
キーワード：spintronics
A two-dimensional electron gas (2DEG) system in a GaAs-based heterostructure is an attractive platform for spintronics, since it exhibits high mobility and its spin-orbit interaction can be modulated by a gate voltage [1]. Thus, the 2DEG is a possible candidate of an electric-gate-controlled spin transistor [2]. However, room temperature (RT) spin transport through the 2DEG has not been realized. The purpose of this study is to achieve the first spin transport through the 2DEG in an GaAs/AlGaAs interface at RT.
In order to confirm the quality of 2DEG of our sample, we observed the Shubnikov-de Haas oscillation at 1.8 K and the Hall resistance at RT. The sheet carrier density of the 2DEG was estimated to be 2.3× 1011 cm-2 at 1.8 K and 1.95 × 1011 cm-2 at RT, which indicates the 2DEG is successfully formed. In the spin transport experiment, we used spin pumping from Ni80Fe20 to the 2DEG. The generated spin current propagated through the 2DEG spin channel of 1 µm in length, and was detected by the inverse spin Hall effect (ISHE) in a Pt electrode. Polarity of the electromotive force due to the ISHE was reversed together with magnetization of the Ni80Fe20, which is in agreement with the symmetry of the ISHE. This corroborates the successful spin transport in the 2DEG in an GaAs/AlGaAs interface at RT.
[1] J. Nitta, T. Akazaki, H. Takayanagi, and T. Enoki, Phys. Rev. Lett. 78, 1335 (1997).
[2] S. Datta and B. Das, Appl. Phys. Lett. 56, 665 (1990)
In order to confirm the quality of 2DEG of our sample, we observed the Shubnikov-de Haas oscillation at 1.8 K and the Hall resistance at RT. The sheet carrier density of the 2DEG was estimated to be 2.3× 1011 cm-2 at 1.8 K and 1.95 × 1011 cm-2 at RT, which indicates the 2DEG is successfully formed. In the spin transport experiment, we used spin pumping from Ni80Fe20 to the 2DEG. The generated spin current propagated through the 2DEG spin channel of 1 µm in length, and was detected by the inverse spin Hall effect (ISHE) in a Pt electrode. Polarity of the electromotive force due to the ISHE was reversed together with magnetization of the Ni80Fe20, which is in agreement with the symmetry of the ISHE. This corroborates the successful spin transport in the 2DEG in an GaAs/AlGaAs interface at RT.
[1] J. Nitta, T. Akazaki, H. Takayanagi, and T. Enoki, Phys. Rev. Lett. 78, 1335 (1997).
[2] S. Datta and B. Das, Appl. Phys. Lett. 56, 665 (1990)