Presentation Information

[25p-71B-9]Changes in Transport and Magnetic properties of a van der Waals Ferromagnetic Material induced by Heavy Ion Irradiation

〇(D)Siyue Zhang1, Kazuya Harii2, Tomoyuki Yokouchi1, Satoru Okayasu3, Yuki Shiomi1 (1.Department of Basic Science, The univ. of Tokyo, 2.National Inst. for Quantum Science and Technology, 3.Japan Atomic Energy Agency)


2D materials,amorphous ferromagnetic metal,heavy-ion irradiation

Since the breakthrough of graphene in 2004, van der Waals materials (2D materials) have attracted much interest because of their distinct physical properties compared to conventional bulk materials, such as high electron mobility and superconductivity induced by twist engineering. However, in line with the Mermin-Wagner theorem, 2D magnetic materials had not been experimentally discovered until recently. In 2017, it was found that a typical 2D ferromagnetic semiconductor, CrGeTe3, exhibits an intrinsic ferromagnetic order down to the bilayer limit, sparking extensive research in the field of 2D materials. In the research field of phase-change materials, CrGeTe3 was recently demonstrated to be a good phase-change material exhibiting an inverse resistance change during phase transformation, with low resistance in the amorphous phase (a-CrGT) and high resistance in the crystalline phase (c-CrGT) . This phenomenon has been observed in thin films and bulk materials using electric pulse quenching and high pressure (~30 GPa), respectively. However, comprehensive experiments to investigate the physical mechanisms behind this phenomenon are lacking. In this study, we used heavy-ion irradiation methods to prepare a-CrGT and experimentally investigated the transport and magnetic properties of the two phases.