Effects of swift heavy ion irradiation on magnetic properties of Fe-Rh alloy

Fukuzumi, Masafumi*; Chimi, Yasuhiro; Ishikawa, Norito; Suzuki, Motohiro*; Takagaki, Masafumi*; Mizuki, Junichiro; Ono, Fumihisa*; Neumann, R.*; Iwase, Akihiro*

Nuclear Instruments and Methods in Physics Research B, 245(1), p.161 - 165, 2006/04

https://doi.org/10.1016/j.nimb.2005.11.094

We have performed swift heavy ion irradiations in Fe-50at.%Rh alloys at room temperature. Before and after the irradiations, the magnetic properties and the lattice structure are measured using Superconducting QUantum Interference Device (SQUID) and X-Ray Diffractometer (XRD), respectively. We have also performed X-ray Magnetic Circular Dichroism (XMCD) measurement near the Fe K-edge at the synchrotron radiation facility, SPring-8, to examine the irradiation-induced ferromagnetic state near the specimen surface. We have found that the swift heavy ion irradiations induce the ferromagnetic state in Fe-50at.%Rh alloy below the antiferromagnetism-ferromagnetism transition temperature of the unirradiated alloy and the lattice expasion by 0.3%. For the specimens irradiated with swift heavy ions, we observe the XMCD spectra correponding to ferromagnetisim, which depend on the mass of irradiating ions and/or irradiation fluence. Effects of energy loss through electronic excitation and elastic collisions on lattice and magnetic structures of Fe-Rh alloy are discussed.