Study on ferromagnetic ordering of FeRh thin films induced by energetic heavy ion irradiation by means of X-ray magnetic circular dichroism

Aiko, Kazuma*; Toki, Atsushi*; Okuda, Shuichi*; Saito, Yuichi; Kamiya, Tomihiro; Nakamura, Tetsuya*; Kinoshita, Toyohiko*; Iwase, Akihiro*; Matsui, Toshiyuki*

The ion irradiation induced magnetic state of the FeRh thin films with 10 MeV Iodine ion beam has been investigated by the measurements of a superconducting quantum interference device (SQUID) magnetometer and soft X-ray magnetic circular dichroism (XMCD). It was clearly shown in the magnetization loops by SQUID measurements that the ion irradiation induced ferromagnetic state in the FeRh thin films even below room temperature. This was also confirmed by the XMCD measurements. However ion irradiation fluence dependence on magnetic state at the sample surface measured by XMCD was totally different from that by use of SQUID. Moreover, it was revealed by XMCD sum rule analysis that the ion irradiation induced ferromagnetism of FeRh thin films was mainly dominated by the spin moment.