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arXiv · 1908.10807

Pronounced 2/3 magnetization plateau in a frustrated $S$ = 1 isolated spin-triangle compound: Interplay between Heisenberg and biquadratic exchange interactions

S. Chattopadhyay·B. Lenz·S. Kanungo·Sushila·S. K. Panda·S. Biermann·W. Schnelle·K. Manna·R. Kataria·M. Uhlarz·Y. Skourski·S. A. Zvyagin·A. Ponomaryov·T. Herrmannsdörfer·R. Patra·J. Wosnitza
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Abstract

We report the synthesis and characterization of a new quantum magnet [2-[Bis(2-hydroxybenzyl)aminomethyl]pyridine]Ni(II)-trimer (BHAP-Ni3) in single-crystalline form. Our combined experimental and theoretical investigations reveal an exotic spin state that stabilizes a robust 2/3 magnetization plateau between 7 and 20 T in an external magnetic field. AC-susceptibility measurements show the absence of any magnetic order/glassy state down to 60 mK. The magnetic ground state is disordered and specific-heat measurements reveal the gapped nature of the spin excitations. Most interestingly, our theoretical modeling suggests that the 2/3 magnetization plateau emerges due to the interplay between antiferromagnetic Heisenberg and biquadratic exchange interactions within nearly isolated spin $S$ = 1 triangles.

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S. Chattopadhyay, B. Lenz, S. Kanungo, Sushila, S. K. Panda, S. Biermann, W. Schnelle, K. Manna, R. Kataria, M. Uhlarz, Y. Skourski, S. A. Zvyagin, A. Ponomaryov, T. Herrmannsdörfer, R. Patra, J. Wosnitza. 2019-08-28. Pronounced 2/3 magnetization plateau in a frustrated $S$ = 1 isolated spin-triangle compound: Interplay between Heisenberg and biquadratic exchange interactions. https://doi.org/10.1103/physrevb.100.094427

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