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arXiv · 1702.08254

Single-component molecular material hosting antiferromagnetic and spin-gapped Mott subsystems

Rina Takagi·Takamasa Hamai·Hiro Gangi·Kazuya Miyagawa·Biao Zhou·Akiko Kobayashi·Kazushi Kanoda
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Abstract

We investigated a system based solely on a single molecular species, Cu(tmdt)$_{2}$, accommodating $d$ and $π$ orbitals within the molecule. $^{13}$C nuclear magnetic resonance measurements captured singlet-triplet excitations of $π$ spins indicating the existence of a $π$-electron-based spin-gapped Mott insulating subsystem, which has been hidden by the large magnetic susceptibility exhibited by the $d$ spins forming antiferromagnetic chains. The present results demonstrate a unique hybrid Mott insulator composed of antiferromagnetic and spin-singlet Mott subsystems with distinctive dimensionalities.

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Rina Takagi, Takamasa Hamai, Hiro Gangi, Kazuya Miyagawa, Biao Zhou, Akiko Kobayashi, Kazushi Kanoda. 2017-02-27. Single-component molecular material hosting antiferromagnetic and spin-gapped Mott subsystems. https://doi.org/10.1103/physrevb.95.094420

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