Critical phenomenon of the ferromagnet Cr 2 Te 3 with strong perpendicular magnetic anisotropy

作者：Aina Wang, Zan Du, Fanying Meng, Azizur Rahman, Wei Liu, Jiyu Fan, Chunlan Ma, Langsheng Ling, Chuanying Xi, Min Ge, Li Pi, Yuheng Zhang, Lei Zhang · 发表于：Physical Review Applied · 年份：2024 · DOI：10.1103/physrevapplied.22.034006 · 被引用次数：8 · 研究领域：2D Materials and Applications、Topological Materials and Phenomena、Heusler alloys: electronic and magnetic properties

Chromium telluride ${\mathrm{Cr}}_{x}{\mathrm{Te}}_{y}$ has great potential applications in spintronics due to its intrinsic ferromagnetism and strong magnetic anisotropy. In this study, we systematically investigate magnetic properties of a ferromagnetic ${\mathrm{Cr}}_{2}{\mathrm{Te}}_{3}$ single crystal with strong perpendicular magnetic anisotropy (PMA). Apart from ferromagnetic-to-paramagnetic (FM-PM) transitions at ${T}_{C}\ensuremath{\sim}181$ K for both $H//c$ and $H//ab$, other exotic magnetic behaviors are revealed, such as a field-modulated first-order transition uncovered by the anisotropic magnetization, a canted FM coupling rather than previously reported spin-glass behavior demonstrated by the ac susceptibility. Furthermore, anisotropic magnetization reveals significant PMA stronger than any other $\mathrm{Cr}$-based transition metal chalcogenide, with a negligible saturation field for $H//c$ but a distinct one up to 155 kOe for $H//ab$. Critical exponents $\ensuremath{\beta}=0.340(5)$, $\ensuremath{\gamma}=1.114(1)$, and $\ensuremath{\delta}=4.504(5)$ are obtained for $H//c$, which fall between the three-dimensional (3D)-$XY$ and 3D-Ising models indicative of anisotropic magnetic coupling. An $H$-$T$ phase diagram of the ${\mathrm{Cr}}_{2}{\mathrm{Te}}_{3}$ single crystal is constructed for $H//c$, which distinguishes canted FM1, canted FM2, forced FM (FFM), and PM phases. The phase diagram indicates that the transition to the canted FM2 under lower fields is ...