Phase transitions and magnetic properties of LuFe2O4 under pressure

Abstract

The effect of hydrostatic pressure on complex magnetic phase diagram of $\mathrm{LuF}{\mathrm{e}}_{2}{\mathrm{O}}_{4}$ has been investigated by various magnetic measurements in the range of 0--12 kbar. The temperature of the ferrimagnetic (fM) transition (${T}_{\mathrm{N}}\ensuremath{\approx}245\phantom{\rule{0.16em}{0ex}}\mathrm{K}$) practically does not change with increasing pressure, while the temperature of the appearance of mixed fM and antiferromagnetic (AFM) state at $\ensuremath{\sim}\phantom{\rule{0.16em}{0ex}}200\phantom{\rule{0.16em}{0ex}}\mathrm{K}$ increases with the rate $d{T}_{\mathrm{C}}/dP\ensuremath{\approx}0.8\phantom{\rule{0.16em}{0ex}}\mathrm{K}/\mathrm{kbar}$. Moreover, an applied pressure suppresses the magnetization, enhances the field of metamagnetic transition, and extends the range of existence of mixed fM and AFM state. Suppression of the ordered magnetic moment under pressure induces a transition from a counterclockwise (CCW) thermal hysteresis below $T\ensuremath{\approx}220\phantom{\rule{0.16em}{0ex}}\mathrm{K}$ to a clockwise (CW) thermal hysteresis in a magnetic field $H=1\phantom{\rule{0.16em}{0ex}}\mathrm{kOe}$. Nevertheless, field induced metamagnetic transition from mixed fM and AFM state to fM state results in a narrowing of the temperature range of thermal hysteresis and in restoring of CCW type of thermal hysteresis. As a consequence of metamagnetic transition, the thermal hysteresis completed at $H=10\phantom{\rule{0.16em}{0ex}}\mathrm{kOe}$ remains one of the CCW type under applied pressure.