It is known that the zircon-type orthovanadates $\mathrm{RV}{\mathrm{O}}_4$ show promise in many different applications as catalysts and optical materials. In this work, we demonstrate that the $\mathrm{TbV}{\mathrm{O}}_4$ compound can be also used as magnetic refrigerant in efficient and ecofriendly cryocoolers due to its strong magnetocaloric effect at low-temperature regime. The application of a relatively low magnetic field of 2 T along the easy magnetization axis ($a$) gives rise to a maximum entropy change of about 20 J/kg K at 4 K. More interestingly, under sufficiently high magnetic fields, the isothermal entropy change $-\mathrm{\Delta }{S}_{\mathrm{T}}$ remains approximately constant over a wide temperature range which is highly appreciated from a practical point of view. In the magnetic field change of 7 T, $-\mathrm{\Delta }{S}_{\mathrm{T}}$ that reaches roughly 22 J/kg K remains practically unchanged between 0 and 34 K leading to an outstanding refrigerant capacity of about 823 J/kg. On the other hand, the lowering of crystallographic symmetry from the tetragonal to the orthorhombic structure occurring close to 33 K as confirmed by Raman scattering data results in a strong magnetic anisotropy. Accordingly, strong thermal effects can be also obtained simply by spinning the $\mathrm{TbV}{\mathrm{O}}_4$ single crystals between their hard and easy orientations in constant magnetic fields instead of the standard magnetization-demagnetization process. Such rotating magnetocaloric effects would open the way for the implementation of $\mathrm{TbV}{\mathrm{O}}_4$ in a new generation of compact and simplified magnetic refrigerators that can be dedicated to the liquefaction of hydrogen and helium.

中文翻译：

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在很宽的低温温度范围内，TbVO4晶体具有很强的常规和旋转磁热效应

已知锆石型原钒酸盐 $\mathrm{房车}{\mathrm{Ø}}_4$在催化剂和光学材料的许多不同应用中显示出希望。在这项工作中，我们证明了$\mathrm{病毒}{\mathrm{Ø}}_4$由于其在低温条件下的强磁热效应，该化合物还可以在高效，环保的低温冷却器中用作磁性制冷剂。沿易磁化轴施加2 T的相对较低的磁场（$\mathrm{一种}$）在4 K时产生的最大熵变化约为20 J / kgK。更有趣的是，在足够高的磁场下，等温熵的变化 $-\mathrm{\Delta }{\mathrm{小号}}_{\mathrm{Ť}}$在很宽的温度范围内保持近似恒定，这从实际的角度来看是值得赞赏的。在7 T的磁场变化中$-\mathrm{\Delta }{\mathrm{小号}}_{\mathrm{Ť}}$达到约22 J / kg K的温度在0到34 K之间几乎保持不变，从而导致出色的制冷剂容量约823 J / kg。另一方面，如通过拉曼散射数据所证实的，在接近33K处发生的从四方结构到正交结构的晶体对称性的降低导致强的磁各向异性。因此，仅通过旋转纺丝就可以获得强的热效应。$\mathrm{病毒}{\mathrm{Ø}}_4$在恒定磁场中硬和易取向之间的单晶，而不是标准的磁化-消磁过程。这种旋转的磁热效应将为实施$\mathrm{病毒}{\mathrm{Ø}}_4$ 新一代紧凑，简化的磁性冰箱，可专门用于氢气和氦气的液化。