The evolution of Weyl nodes in Ni doped thallium niobate pyrochlore Tl${}_{2-x}$Ni${}_x$Nb${}_2$O${}_7$

Abstract

Magnetic Weyl semimetal (WSM) is of great importance both for fundamental physics and potential applications due to its spontaneous magnetism, robust band topology, and enhanced Berry curvature. It possesses many unique quantum effects, including large intrinsic anomalous Hall effect, Fermi arcs, and chiral anomaly. In this work, using ab initio calculations, we propose that Ni doped pyrochlore Tl${}_2$Nb${}_2$O${}_7$ is a magnetic WSM caused by exchange field splitting on bands around its quadratic band crossing point. The exchange field tuned by Ni 3d on-site Coulomb interaction parameter $U$ drives the evolution of Weyl nodes and the resulting topological phase transition. Since Weyl nodes can exist at generic point in Brillouin zone and are hard to be exactly identified, the creation and annihilation of them, i.e., the change in their number, chirality and distribution, have been consistently confirmed with a combined theoretical approach, which employs parity criterion, symmetry indicator analysis and the Wilson loop of Wannier center. We find that Weyl nodes remain in a quite large range of $U$ and are close to Fermi level, which makes the experimental observation very possible. We think this method and our proposal of magnetic WSM will be useful in finding more WSMs and adding our understanding on the topological phase transition.

References in corpus (33)

• Maximally-localized generalized Wannier functions for composite energy bands
• Electronic Structure of Pyrochlore Iridates: From Topological Dirac Metal to Mott Insulator
• Topological Insulators with Inversion Symmetry
• Experimental Observation of the Quantum Anomalous Hall Effect in a Magnetic Topological Insulator
• WannierTools: An open-source software package for novel topological materials
• Quantized Anomalous Hall Effect in Magnetic Topological Insulators
• Maximally-localized Wannier functions for entangled energy bands
• Chern semi-metal and Quantized Anomalous Hall Effect in HgCr2Se4
• Giant anomalous Hall effect in a ferromagnetic Kagome-lattice semimetal
• Phase transition between the quantum spin Hall and insulator phases in 3D: emergence of a topological gapless phase
• Magnetic Weyl Semimetal Phase in a Kagome Crystal
• Fermi-arc diversity on surface terminations of the magnetic Weyl semimetal Co3Sn2S2
• Large intrinsic anomalous Hall effect in half-metallic ferromagnet Co3Sn2S2 with magnetic Weyl fermions
• Discovery of topological Weyl fermion lines and drumhead surface states in a room temperature magnet
• Quantum anomalous Hall effect and related topological electronic states
• Giant anisotropic nonlinear optical response in transition metal monopnictide Weyl semimetals
• High-throughput calculations of magnetic topological materials
• First Principles Studies on 3-Dimentional Strong Topological Insulators: Bi2Te3, Bi2Se3 and Sb2Te3
• Colossal Bulk Photovoltaic Effect in a Weyl Semimetal
• Topological Weyl semimetals in the chiral antiferromagnetic materials Mn3Ge and Mn3Sn
• Time-Reversal-Breaking Weyl Fermions in Magnetic Heusler Alloys
• Heusler, Weyl, and Berry
• Berry Curvature Enhanced Nonlinear Photogalvanic Response of Type-II Weyl Cone
• Chiral terahertz wave emission from the Weyl semimetal TaAs
• Room-Temperature Terahertz Anomalous Hall Effect in Weyl Antiferromagnet Mn${}_3$Sn Thin Films
• Topological correspondence between magnetic space group representations
• Topological classification and diagnosis in magnetically ordered electronic materials
• Spin Excitations and Spin Wave Gap in the Ferromagnetic Weyl Semimetal Co${}_3$Sn${}_2$S${}_2$
• Gap closing and universal phase diagrams in topological insulators
• Evolution of Berry curvature and reentrant quantum anomalous Hall effect in an intrinsic magnetic topological insulator
• High-throughput screening for Weyl Semimetals with S${}_4$ Symmetry
• Topological phases in pyrochlore thallium niobate Tl${}_2$Nb${}_2$O${}_{6+x}$
• Unprotected quadratic band crossing points and quantum anomalous Hall effect in FeB2 monolayer

Cited by in corpus (3)

• Structure, physical properties, and magnetically tunable topological phases in topological semimetal EuCuBi
• Weyl points and anomalous transport effects tuned by the Fe doping in Mn${}_3$Ge Weyl semimetal
• Topological States in Chevrel Phase Materials from First-principle Calculations