09:30 〜 09:45
▼ [20a-D104-3] Electrical control of ferromagnetism in the n-type ferromagnetic semiconductor (In,Fe)Sb with high Curie temperature
キーワード：ferromagnetic semiconductors, Electrical control of ferromagnetism, high Curie temperature
Electrical control of ferromagnetism in magnetic materials has attracted much attention, since it offers not only an opportunity to investigate many fundamental aspects of ferromagnetism but also a promising method for ultra-low-power magnetization switching, which is a key technology for low-power magnetic memory devices. Pioneering studies on electrical control of ferromagnetism have been performed on ferromagnetic semiconductors (FMSs), since they possess both semiconducting and ferromagnetic properties and their carrier concentrations are low enough to allow electrical manipulation of ferromagnetism. There have been many reports on the electrical control ferromagnetism in III-V, II-V, and group IV based ferromagnetic semiconductor FMSs. However, most of these studies were performed at temperatures lower than 110 K due to the limitation of their Curie temperatures (TC).
In this work, we demonstrate electrical control ferromagnetism at high temperature (210 K) in the new n-type ferromagnetic semiconductors (In,Fe)Sb with high TC. An electric double layer transistor (EDLT) with a (In0.89,Fe0.11)Sb thin film channel are used to investigate the ferromagnetic properties under electrical gating. A liquid electrolyte is used instead of a conventional solid gate to obtain a large change (40%) of the electron density in the (In0.89,Fe0.11)Sb channel. The anomalous Hall resistance (which is proportional to the magnetization) can be controlled by the gate electric field at high temperature, and TC of the (In,Fe)Sb thin film can be changed by 7 K by applying a small gate-source voltage (VGS = +5 V). This result indicates that magnetization as well as ferromagnetic phase transition can be modulated by gate electric field, and high-TC (In,Fe)Sb is an intrinsic electron-induced FMS. Note that ferromagnetism at room temperature has been recently demonstrated in (In,Fe)Sb with TC = 335 K. Therefore, our result paves a way for realizing semiconductor spintronic devices operating at room temperature with low power consumption.
In this work, we demonstrate electrical control ferromagnetism at high temperature (210 K) in the new n-type ferromagnetic semiconductors (In,Fe)Sb with high TC. An electric double layer transistor (EDLT) with a (In0.89,Fe0.11)Sb thin film channel are used to investigate the ferromagnetic properties under electrical gating. A liquid electrolyte is used instead of a conventional solid gate to obtain a large change (40%) of the electron density in the (In0.89,Fe0.11)Sb channel. The anomalous Hall resistance (which is proportional to the magnetization) can be controlled by the gate electric field at high temperature, and TC of the (In,Fe)Sb thin film can be changed by 7 K by applying a small gate-source voltage (VGS = +5 V). This result indicates that magnetization as well as ferromagnetic phase transition can be modulated by gate electric field, and high-TC (In,Fe)Sb is an intrinsic electron-induced FMS. Note that ferromagnetism at room temperature has been recently demonstrated in (In,Fe)Sb with TC = 335 K. Therefore, our result paves a way for realizing semiconductor spintronic devices operating at room temperature with low power consumption.