The electronic dynamics in ${\mathrm{Nb}}_{2n+1}{\mathrm{Si}}_n{\mathrm{Te}}_{4n+2}$ with varying component $n$ are systematically investigated by low-temperature scanning tunneling microscopy/spectroscopy (STM/STS). Our quasiparticle interferences reveal a nondecay standing wave at the Fermi level, proving the one-dimensional (1D) nature of the charge carriers (holes) in the materials. The energy and component dependence of phase relaxation length $l_{\varphi }$ and lifetime $\tau$ of 1D holes are unveiled and found to be consistent with the Tomonaga-Luttinger liquid theory. Our work demonstrates ${\mathrm{Nb}}_{2n+1}{\mathrm{Si}}_n{\mathrm{Te}}_{4n+2}$ as a platform to manipulate 1D physics and offers an alternative perspective for studying electronic dynamics of non-Fermi liquids through STM experiments.

• Received 4 June 2022
• Revised 15 August 2022
• Accepted 17 August 2022

DOI:https://doi.org/10.1103/PhysRevB.106.085426