Critical behavior and anisotropic magnetocaloric effect of the quasi-one-dimensional hexagonal ferromagnet <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>Pr</mml:mi><mml:mi>Cr</mml:mi><mml:msub><mml:mi>Ge</mml:mi><mml:mn>3</mml:mn></mml:msub></mml:mrow></mml:math>
Xiaojun Yang, Junxiao Pan, Shijiang Liu, Mao Yang, Leiming Cao, Dongliang Chu, Kexi Sun
Abstract
Critical properties and anisotropic magnetocaloric effect of hexagonal ferromagnet $\mathrm{Pr}\mathrm{Cr}{\mathrm{Ge}}_{3}$ single crystals were investigated. The critical exponents $\ensuremath{\beta}=0.352$ with a critical temperature ${T}_{C}=90.5\phantom{\rule{0.28em}{0ex}}\mathrm{K}$ and $\ensuremath{\gamma}=1.026$ with ${T}_{C}=90.6\phantom{\rule{0.28em}{0ex}}\mathrm{K}$ are obtained by the modified Arrott plot, whereas $\ensuremath{\delta}=3.98$ is deduced by a critical isotherm analysis. The critical exponents suggest a long-range magnetic coupling with the exchange distance decaying as $J(r)\ensuremath{\sim}{r}^{\ensuremath{-}4.6}$. Furthermore, the magnetic entropy change $\ensuremath{-}\mathrm{\ensuremath{\Delta}}{S}_{M}$ reaches a maximum value around ${T}_{C}$, i.e., $\ensuremath{-}\mathrm{\ensuremath{\Delta}}{S}_{M}\ensuremath{\sim}3.2(1.8)\phantom{\rule{0.28em}{0ex}}\mathrm{J}\phantom{\rule{0.28em}{0ex}}{\mathrm{kg}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{K}}^{\ensuremath{-}1}$ with in-plane (out-of-plane) field change of 5 T, verifying large magnetic anisotropy. The rescaled $\ensuremath{-}\mathrm{\ensuremath{\Delta}}{S}_{M}(T,H)$ plots collapse onto a universal curve independent of temperature and field, confirming a second-order magnetic phase transition and reliability of the obtained critical exponents.