講演情報
[19p-C501-11]Scaling of the anomalous Hall effect of MBE-grown Cr2Te3 thin films
〇Yujun Wang1, Kawaguchi Masashi1, Shunzhen Wang1, Jun Uzuhashi2, Tadakatsu Ohkubo2, Masamitsu Hayashi1 (1.The Univ. of Tokyo, 2.NIMS)
キーワード：
van der Waals materials、anomalous Hall effect、perpendicular magnetic anisotropy
We performed a systematic study on the magneto-transport properties of Cr2Te3 thin films. Cr2Te3 is a van der Waals type layered structure with unique ferromagnetic characteristics. Studies have shown that the Curie temperature of Cr2Te3 can reach room temperature with the increase of film thickness. We have grown Cr2Te3 thin films using molecular beam epitaxy (MBE). The film structure is characterized by RHEED, scanning transmission electron microscope (STEM) and X-ray diffraction (XRD). The RHEED patterns show sharp streaks during the growth, indicating the smooth surface of the films. A 2:3 ratio of Cr and Te is confirmed from STEM measurement. Typical Bragg diffraction peaks associated with the hexagonal (0001) planes are observed in XRD spectrum. The position and amplitude of the peaks are in good agreement with tabulated data in the database, suggesting successful preparation of high quality Cr2Te3 films.
The magneto-transport properties of the films were studied using micro-fabricated Hall bars. The anomalous Hall resistance RAH is measured against the out of plane magnetic field. A square hysteresis loop is observed at low temperature, indicating the existence of the ferromagnetic phase. The Curie temperature of the films is ~175 K. RAH is found to vary with the measurement temperature. Interestingly, the sign of RAH changes as the temperature is increased. To identify the origin of the sign change, we studied the resistivity ρxx dependence of RAH. From these results, we discuss possible contributions to the anomalous Hall resistance which causes its sign change. Details of the analysis will be discussed in the presentation.
The magneto-transport properties of the films were studied using micro-fabricated Hall bars. The anomalous Hall resistance RAH is measured against the out of plane magnetic field. A square hysteresis loop is observed at low temperature, indicating the existence of the ferromagnetic phase. The Curie temperature of the films is ~175 K. RAH is found to vary with the measurement temperature. Interestingly, the sign of RAH changes as the temperature is increased. To identify the origin of the sign change, we studied the resistivity ρxx dependence of RAH. From these results, we discuss possible contributions to the anomalous Hall resistance which causes its sign change. Details of the analysis will be discussed in the presentation.