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arXiv · 1710.04028

Weak ferromagnetism and glassy state in kappa-(BEDT-TTF)2Hg(SCN)2Br

M. Hemmida·H. -A. Krug von Nidda·B. Miksch·L. L. Samoilenko·A. Pustogow·S. Widmann·A. Henderson·T. Siegrist·J. Schlueter·A. Loidl·M. Dressel
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Abstract

Since the first observation of weak ferromagnetism in the charge-transfer salt kappa-(BEDT-TTF)2-Cu[N(CN)2]Cl [U. Welp et al., Phys. Rev. Lett. 69, 840 (1992)], no further evidence of ferromagnetism in this class of organic materials has been reported. Here we present static and dynamic spin susceptibility measurements on kappa-(BEDT-TTF)2Hg(SCN)2Br revealing weak ferromagnetism below about TWF = 20 K. We suggest that frustrated spins in the molecular dimers suppress long-range order, forming a spin-glass ground state in the insulating phase.

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M. Hemmida, H. -A. Krug von Nidda, B. Miksch, L. L. Samoilenko, A. Pustogow, S. Widmann, A. Henderson, T. Siegrist, J. Schlueter, A. Loidl, M. Dressel. 2018-12-07. Weak ferromagnetism and glassy state in kappa-(BEDT-TTF)2Hg(SCN)2Br. https://doi.org/10.1103/physrevb.98.241202

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