[8p-A413-1~7] 10.4 Semiconductor spintronics, superconductor, multiferroics

▼ [8p-A413-5] Improved performance of GaMnAs-based vertical spin electric double-layer transistors

〇Hiroki Yamasaki¹, Toshiki Kanaki¹, Hiroshi Terada¹, Yoshihiro Iwasa¹, Shinobu Ohya^1,2, Masaaki Tanaka^1,2 (1.Univ. of Tokyo, 2.CSRN Univ. of Tokyo)

Keywords:spin MOSFET, ferromagnetic semiconductor

In this study, we fabricated GaMnAs-based vertical spin EDLTs, which are composed of GaMnAs/ GaAs / GaMnAs / GaAs:Be heterostructure from the top to the bottom, grown on a p+GaAs(001) substrate. After the growth, we fabricated elongated-shaped mesas. We applied a gate voltage via ionic liquid because the ionic liquid has larger capacitance than solid gate oxides, and thus our vertical spin EDLTs are anticipated to show high current controllability. In this study, we observed a MR ratio up to 36% at 3.8 K. In addition, the coercive force of the GaMnAs layer was modulated by about 0.5 mT by the gate-source voltage. Moreover, the current modulation was enhanced up to 20% by using ionic liquid. These results indicate that comb-shaped mesas and ionic liquid are effective and that narrowing the width of the elongated mesas can enhance the current controllability.