Pressure-Induced Magnetic Transition in Fe₄N Probed by Fe<i>K</i>-edge XMCD Measurement

Abstract

X-ray magnetic circular dichroism (XMCD) of γ'-iron nitride (Fe 4 N) was recorded at Fe K -edge under high pressue up to 27 GPa. The XMCD intensity decreased remarkably with pressure, and vanished at 24 GPa. Compressibility was measured by the X-ray diffraction method. These results indicate that Fe 4 N undergoes a second-order phase transition from the ferromagnetic state to a paramagnetic state without any structural change. The pressure-induced demagnetizing process is discussed in terms of the Fe magnetic states in the local environment.