PHYSICAL REVIEW B 110, 195153 (2024) Topological nodal line features in NiSe semimetal: Insights from electronic transport and density functional theory studies Sharadnarayan Pradhan , 1 Sanand Kumar Pradhan , 1 Priyanath Mal , 2 P. Rambabu, 1 Archana Lakhani, 3 Bipul Das, 4 Bheema Lingam Chittari , 5 G. R. Turpu , 1 and Pradip Das 1 , * 1 Department of Pure and Applied Physics, Guru Ghasidas Vishwavidyalaya, Koni, Bilaspur, Chhattisgarh 495009, India 2 Department of Physics and Photon Science, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea 3 UGC-DAE CSR, University Campus, Khandwa Road, Indore, Madhya Pradesh 452001, India 4 Department of Physics, National Taiwan Normal University, Taipei City 106, Taiwan 5 Department of Physical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India (Received 17 May 2024; revised 13 September 2024; accepted 5 November 2024; published 27 November 2024) The linear band touchings at one-dimensional lines or rings that characterize a nodal line semimetal phase have created much interest in research as they may find use in the next generation of low-dissipation electronics and spintronics. Here we demonstrated the presence of multiple scattering processes including electron-phonon (e- p) and Mott’s interband scattering within a single crystal of nickel selenide (NiSe) using temperature-dependent resistivity data fitted to Bloch-Gruneisen-Mott formula. Multiple scattering mechanisms were further validated from the observation of transverse magnetoresistance (MR) data that displayed a well scaled in extended Kohler’s rule and a deviation from Kohler’s rule. Temperature-dependent resistivityat different magnetic fields indicate topological semimetallic nature of NiSe. The observed negative magnetoconductivity data fitted to the Hikami-Larkin-Nagaoka equation describes weak antilocalization. The weak field magnetoconductivity follows the −ln(B) scaling behavior, indicating the topological nodal line feature. The density functional theory (DFT) calculations support the marginal domination of electron concentration over hole concentration. The experimental observation of nonlinear Hall resistivity with negative slope indicates that electrons are dominating. It is plausible that the finding of low MR is the result of the size of electron pockets is slightly larger than that of hole pockets. Five different types of nodal lines having π -Berry phase without spin orbit coupling (SOC) are presented as revealed from the DFT calculations: one infinite endless, one diamond-shaped, two with sixfold rotational symmetry, and one with threefold rotational symmetry. All nodal lines stack perpendicular to the crystallographic c axis, with the exception of the diamond-shaped nodal line. The DFT calculations also manifest the two nodal lines which are still protected in the presence of SOC. DOI: 10.1103/PhysRevB.110.195153 I. INTRODUCTION A new family of quantum materials known as nodal line semimetals, characterized by topological band-crossings, was discovered subsequent to the discoveries of topological insulators [1–3], Dirac [4,5], and Weyl semimetals [6,7]. Nodal line semimetals can be viewed as precursors to other topological states [8]. For instance, the presence of spin-orbit coupling (SOC) can transform these nodal line states into Weyl or Dirac points, or a topological insulator states [9,10], giving rise to transport phenomena such as high magnetoresistance (MR), high mobility, chiral anomaly, giant anomalous Hall effect, nonlinear Hall effect and a nontrivial π -Berry phase [10–14], etc. In PbTaSe 2 , the ring-shaped topological nodal lines states linked to the drumhead-like surface states are observed to be protected by the reflection symmetry [15]. Several materials have been identified as nodal line semimetals, including ZrSiX(X = S, Se,Te) [16], CaAgAs [17], CaCdSn [18], YbCdGe [19] SnTaS 2 [20], In x TaS 2 [21], TlTaSe 2 [22], InNbX 2 [23], InBi * Contact author: pradipd.iitb@gmail.com [24], and SrAs 3 [25], among others. However, many of these predictions were made without considering spin-orbit interaction and when SOC is included, the nodal line features typically suffer from gap opening [26]. Angle-resolved photoemission spectroscopy (ARPES) has been instrumental in directly observing bulk and surface band structures, while on the other hand, scanning tunneling microscopy (STM) also explored the information from Fermi surfaces [27,28]. Compared to the ARPES and STM, transport measurements offer distinct advantages as the bulk and surface states can be distinctly probed through the intricate design and fabrication of two-dimensional (2D) or 3D electronic devices as well as suitable field manipulations. Furthermore, anomalous transport responses are governed by the nontrivial band topology in topological nodal line semimetals, which is crucial for integrating these materials into sophisticated electronics and spintronics applications. Recently, transition metal chalcogenides and pnictides have been explored for their topological surface states and their diverse magnetic and electronic properties [29]. Nickel selenide (NiSe) has been theoretically predicated to be a topological nodal line semimetal [30], with a hexagonal crystal structure belonging to space group P6 3 /mmc similar to NiAs [31]. Additionally, 2469-9950/2024/110(19)/195153(9) 195153-1 ©2024 American Physical Society