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arXiv · 2308.13199

Robust Luttinger liquid state of 1D Dirac fermions in a van der Waals system Nb$_9$Si$_4$Te$_{18}$

Qirong Yao·Hyunjin Jung·Kijeong Kong·Chandan De·Jaeyoung Kim·Jonathan D. Denlinger·Han Woong Yeom
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Abstract

We report on the Tomonaga-Luttinger liquid (TLL) behavior in fully degenerate 1D Dirac fermions. A ternary van der Waals material Nb$_9$Si$_4$Te$_{18}$ incorporates in-plane NbTe$_2$ chains, which produce a 1D Dirac band crossing Fermi energy. Tunneling conductance of electrons confined within NbTe2 chains is found to be substantially suppressed at Fermi energy, which follows a power law with a universal temperature scaling, hallmarking a TLL state. The obtained Luttinger parameter of ~0.15 indicates strong electron-electron interaction. The TLL behavior is found to be robust against atomic-scale defects, which might be related to the Dirac electron nature. These findings, as combined with the tunability of the compound and the merit of a van der Waals material, offer a robust, tunable, and integrable platform to exploit non-Fermi liquid physics.

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Qirong Yao, Hyunjin Jung, Kijeong Kong, Chandan De, Jaeyoung Kim, Jonathan D. Denlinger, Han Woong Yeom. 2023-08-25. Robust Luttinger liquid state of 1D Dirac fermions in a van der Waals system Nb$_9$Si$_4$Te$_{18}$. https://doi.org/10.1021/acs.nanolett.3c01789

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