Browsing by Author "Ren, WJ"

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    Magnetic ordering in the rhombohedral α-DyGa3
    (Elsevier, 2022-05-15) Cong, MR; Wang, CW; Ren, WJ; Avdeev, M; Ling, CD; Gao, F; Li, B; Zhang, ZD
    We have succeeded in growing α-DyGa3 single crystals by the self-flux method and determined its magnetic structure by neutron powder diffraction. α-DyGa3 crystallizes in the rhombohedral SrSn3-type structure (R3̅m, #166, hR48), and the magnetic sublattice is comprised of staggering layers of triangular lattice of Dy. Magnetic ordering occurs below TN ~ 7.2 K with the magnetic propagation vector k = (1/2, 0, 1/2), results in an alternating stripe antiferromagnetic structure in the ab-plane described by the magnetic space group CC2/c (BNS #15.90, origin at (0, 0, 0)). At 3.5 K, the magnetic moment is 5.72(12) μB per Dy3+. The Dy3+ spins are lying in basal plane and perpendicular to the b-axis. © 2024 Elsevier B.V
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    Ultrasensitive barocaloric material for room-temperature solid-state refrigeration
    (Springer Nature, 2022-04-28) Ren, QY; Qi, J; Yu, DH; Zhang, Z; Song, R; Song, WL; Yuan, B; Wang, TH; Ren, WJ; Zhang, ZD; Tong, X; Li, B
    One of the greatest obstacles to the real application of solid-state refrigeration is the huge driving fields. Here, we report a giant barocaloric effect in inorganic NH4I with reversible entropy changes of ΔSmax P0!P ∼71 J K−1 kg−1 around room temperature, associated with a structural phase transition. The phase transition temperature, Tt, varies dramatically with pressure at a rate of dTt/dP ∼0.79 K MPa−1, which leads to a very small saturation driving pressure of ΔP ∼40 MPa, an extremely large barocaloric strength of ΔSmax P0!P=ΔP∼1.78 J K−1 kg−1 MPa−1, as well as a broad temperature span of ∼41 K under 80 MPa. Comprehensive characterizations of the crystal structures and atomic dynamics by neutron scattering reveal that a strong reorientation-vibration coupling is responsible for the large pressure sensitivity of Tt. This work is expected to advance the practical application of barocaloric refrigeration. © The Author(s) 2022. This article is licensed under a Creative Commons Attribution 4.0 International License.