Structure and magnetic properties of a family of two-leg spin ladder compounds Ba2RE2Ge4O13 (RE = Pr, Nd, and Gd-Ho) with strong rung interaction

Jin Zhou; Andi Liu; Fangyuan Song; Langsheng Ling; Jingxin Li; Wei Tong; Zhengcai Xia; Gaoshang Gong; Yongqiang Wang; Jinkui Zhao; Hanjie Guo; Zhaoming Tian

arXiv · 2409.09686

Structure and magnetic properties of a family of two-leg spin ladder compounds Ba2RE2Ge4O13 (RE = Pr, Nd, and Gd-Ho) with strong rung interaction

Jin Zhou·Andi Liu·Fangyuan Song·Langsheng Ling·Jingxin Li·Wei Tong·Zhengcai Xia·Gaoshang Gong·Yongqiang Wang·Jinkui Zhao·Hanjie Guo·Zhaoming Tian

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Abstract

Compared to the intensive investigation on the 3d transition-metal (TM)-based spin ladder compounds, less attention has been paid to the ones constructed by the rare-earth (RE) ions. Herein, we report a family of RE-based spin ladder compounds Ba2RE2Ge4O13 (RE = Pr, Nd, Gd-Ho) crystallized into the monoclinic structure with the space group C2/c. The RE ions are arranged on a two-leg spin ladder motif along the b-axis, where the rung and leg exchange interactions are bridged via the RE-O-RE pathways and RE-O-Ge-O-RE routes, respectively. Moreover, the much shorter rung distance in the RE2O12 dimer units than the leg distance suggests Ba2RE2Ge4O13 to be a strong-rung spin ladder system. All the synthesized Ba2RE2Ge4O13 (RE = Pr, Nd, Gd-Ho) compounds exhibit the dominant antiferromagnetic (AFM) interactions and absence of magnetic order down to 1.8 K. Among the family members, Ba2Dy2Ge4O13 can be described by Jeff = 1/2 Kramers doublet states, the low temperature specific heat indicates the coexistence of spin dimerized state with broad maximum at ~ 2.4 K and long-range AFM order with TN = 0.81 K. This family of Ba2RE2Ge4O13 compounds thereby provides a rare platform to investigate the novel spin ladder physics constructed by 4f electrons.

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Jin Zhou, Andi Liu, Fangyuan Song, Langsheng Ling, Jingxin Li, Wei Tong, Zhengcai Xia, Gaoshang Gong, Yongqiang Wang, Jinkui Zhao, Hanjie Guo, Zhaoming Tian. 2024-09-15. Structure and magnetic properties of a family of two-leg spin ladder compounds Ba2RE2Ge4O13 (RE = Pr, Nd, and Gd-Ho) with strong rung interaction. https://arxiv.org/abs/2409.09686

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