PHYSICAL REVIEW B 107, 195124 (2023) Anisotropic transport and multiple topology in quasi-one-dimensional ternary telluride NbNiTe 5 Wen-He Jiao , 1 , * Shaozhu Xiao, 2 , † Wei Liu, 2 Yi Liu, 1 Hang-Qiang Qiu, 3 Keqi Xia, 4 Shaolong He, 2 Yuke Li , 4 Guang-Han Cao, 5, 6 and Xiaofeng Xu 1, ‡ 1 Key Laboratory of Quantum Precision Measurement of Zhejiang Province, Department of Applied Physics, Zhejiang University of Technology, Hangzhou 310023, China 2 Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China 3 Department of Applied Physics, Zhejiang University of Science and Technology, Hangzhou 310023, China 4 School of Physics and Hangzhou Key Laboratory of Quantum Matters, Hangzhou Normal University, Hangzhou 311121, China 5 School of Physics, Interdisciplinary Center for Quantum Information, and State Key Lab of Silicon Materials, Zhejiang University, Hangzhou 310058, China 6 Collaborative Innovation Centre of Advanced Microstructures, Nanjing 210093, China (Received 18 January 2023; revised 20 April 2023; accepted 20 April 2023; published 12 May 2023) Topological quantum materials, which feature nontrivial band topology, have been one of the most attractive research topics in condensed-matter physics in recent decades. The low-dimensional topologically nontrivial materials are especially appealing due to the rich implications for topological physics and the potential appli- cations in next-generation spintronic devices. Here, we report the crystal growth, anisotropic magnetotransport, Hall effect, and quantum de Haas–van Alphen (dHvA) oscillations of a quasi-one-dimensional ternary telluride NbNiTe 5 . The pronounced dHvA oscillations under H ‖ b reveal three major oscillation frequencies F α = 136.41 T, F β = 240.34 T, and F γ = 708.03 T and the associated light effective masses of charge carriers. From the angular dependence of dHvA oscillations, we have revealed the identified frequencies exhibit anisotropic character, all of which arise from the holelike Fermi surface sheets formed by band 1 (F α and F β ) and band 2 (F γ ) by comparing with the Fermi surface calculations. First-principles calculations demonstrate that NbNiTe 5 is a candidate of multiple topological material. In addition to the nonsymmorphic symmetry-protected nodal lines and band inversion (anticrossing) induced topological surface states, a ladder of topological gaps with the coexistence of strong and weak topology and a series of induced topological surface states are also identified. DOI: 10.1103/PhysRevB.107.195124 I. INTRODUCTION The field of new topological semimetals (TSMs), i.e., Dirac semimetals (DSMs), Weyl semimetals (WSMs), nodal- line semimetals (NLSMs), and nodal-surface semimetals (NSSMs), has been blossoming ever since the classification of materials based on symmetry and topology has been ex- tended from insulators to metals or semimetals [1,2]. When the symmetry-protected crossing or touching of conduction and valence bands of semimetals can be characterized by a topological invariant [3], the semimetals are referred to as TSMs [4]. In DSMs and WSMs, two doubly or singly degen- erate bands cross each other at discrete zero-dimensional (0D) nodal points and form a fourfold Dirac point or a twofold Weyl point [5–9]. In NLSMs, fourfold or twofold crossings extend along 1D lines, or closed loops, or even chains in momentum space [10,11], in contrast with discrete nodal points in conven- tional DSMs or WSMs. The Dirac or Weyl fermions in those topological materials could manifest themselves in many ex- otic quantum phenomena such as high carrier mobility [12], * whjiao@zjut.edu.cn † xiaoshaozhu@nimte.ac.cn ‡ xuxiaofeng@zjut.edu.cn unusual magnetic transport behaviors [13–15], and nontrivial quantum oscillations [16,17], etc., paving the way for vast material functionalities and applications in future devices and technologies. A Dirac nodal-line state that is robust against spin-orbit coupling (SOC) usually occurs in 3D or at least 2D sys- tems [11,18] and is rarely identified in quasi-1D materials, i.e., 2D systems with in-plane anisotropy [19], because addi- tional crystalline symmetries (e.g., mirror or nonsymmorphic symmetry) are required to protect an extended linelike band crossing [20,21]. Recently, we discovered evidence of non- trivial topological metallic phases via a combination of an experimental study and first-principles calculations in low- dimensional ternary tellurides TaTMTe 5 (TM = Pd,Ni,Pt) [22–24], the 2D atomic layer of which is composed of al- ternating quasi-1D TMTe 2 and TaTe 3 chains. Later, Hao et al . reported the realization of multiple Dirac nodal lines robust against SOC with fourfold degeneracy in TaNiTe 5 by angle-resolved photoemission spectroscopy (ARPES) as a result of the interplay between structural anisotropy and nonsymmorphic symmetry therein [19]. By means of ARPES measurements, we subsequently observed multiple Dirac-like nodal lines at the Brillouin zone boundary of TaPtTe 5 [25]. After theoretical analysis, we also concluded that the nodal lines along the Y -T path and connecting the R points are 2469-9950/2023/107(19)/195124(10) 195124-1 ©2023 American Physical Society