Robust Luttinger Liquid State of 1D Dirac Fermions in a Van der Waals System Nb9Si4Te18

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

doi:10.1021/acs.nanolett.3c01789

Robust Luttinger Liquid State of 1D Dirac Fermions in a Van der Waals System Nb₉Si₄Te₁₈

Nano Lett. 2023 Sep 13;23(17):7961-7967. doi: 10.1021/acs.nanolett.3c01789. Epub 2023 Aug 25.

Authors

Qirong Yao¹, Hyunjin Jung^{1

2}, Kijeong Kong¹, Chandan De¹, Jaeyoung Kim¹, Jonathan D Denlinger³, Han Woong Yeom^{1

2}

Affiliations

¹ Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang 37673, Korea.
² Department of Physics, Pohang University of Science and Technology, Pohang 37673, Korea.
³ Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.

PMID: 37624091
DOI: 10.1021/acs.nanolett.3c01789

Abstract

We report on the Tomonaga-Luttinger liquid (TLL) behavior in fully degenerate 1D Dirac Fermions. A ternary van der Waals material Nb₉Si₄Te₁₈ incorporates in-plane NbTe₂ 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 a 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, 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.

Keywords: 1D Dirac Fermions; Tomonaga-Luttinger liquid; electron−electron interaction; universal temperature scaling; van der Waals material.