Two linear regimes in optical conductivity of a Type-I Weyl semimetal: the case of elemental tellurium

Abstract

Employing high-pressure infrared spectroscopy we unveil the Weyl semimetal phase of elemental Te and its topological properties. The linear frequency dependence of the optical conductivity provides clear evidence for metallization of trigonal tellurium (Te-I) and the linear band dispersion above 3.0 GPa. This semimetallic Weyl phase can be tuned by increasing pressure further: a kink separates two linear regimes in the optical conductivity (at 3.7 GPa), a signature proposed for Type-II Weyl semimetals with tilted cones; this however reveals a different origin in trigonal tellurium. Our density-functional calculations do not reveal any significant tilting and suggest that Te-I remains in the Type-I Weyl phase, but with two valence bandsin the vicinity of the Fermi level. Their interplay giving rise to the peculiar optical conductivity behavior with more than one linear regime. Pressure above 4.3 GPa stabilizes the more complex Te-II and Te-III polymorphs, which are robust metals.

arXiv comment9 pages, 7 figures

References in corpus (19)

• Charge Transport in Weyl Semimetals
• Observation of the Type-II Weyl Semimetal Phase in MoTe2
• Observation of Fermi Arcs in Type-II Weyl Semimetal Candidate WTe2
• Weyl Node and Spin Texture in Trigonal Tellurium and Selenium
• Spectroscopic Evidence of Type II Weyl Semimetal State in WTe2
• Chiral anomaly and optical absorption in Weyl semimetals
• Optical Signatures of Weyl Points in TaAs
• Signatures of a Pressure-Induced Topological Quantum Phase Transition in BiTeI
• Interband optical conductivity of the [001]-oriented Dirac semimetal Cd3As2
• Optical properties of the perfectly compensated semimetal WTe${}_2$
• Band splitting and Weyl nodes in trigonal tellurium studied by angle-resolved photoemission spectroscopy and density functional theory
• Infrared and Raman spectroscopy measurements of a transition in the crystal structure and a closing of the energy gap of BiTeI under pressure
• Pressure-induced deconfinement of the charge transport in the quasi-one-dimensional Mott insulator (TMTTF)_2AsF_6
• Optical signature of Weyl electronic structures in tantalum pnictides Ta$Pn$ ($Pn=$ P, As)
• Optical evidence of type-II Weyl semimetals MoTe${}_2$ and WTe${}_2$
• Optical conductivity of the Weyl semimetal NbP
• Linear-in-frequency optical conductivity in GdPtBi due to transitions near the triple points
• Low-energy excitations in type-II Weyl semimetal Td-MoTe2 evidenced through optical conductivity
• Evidence for Weyl fermions in the elemental semiconductor tellurium

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• Topological Hall effect in CeAlGe
• Probing structural chirality of crystals using high harmonic generation in solids
• A light-induced Weyl semiconductor-to-metal transition mediated by Peierls instability
• Optical conductivity of the type-II Weyl semimetal WTe${}_2$ under pressure
• Intrinsic Orbital Origin for the Chirality-Dependent Nonlinear Planar Hall Effect of Topological Nodal Fermions in Chiral Crystals
• Optical signatures of phase transitions and structural modulation in elemental tellurium under pressure
• Quantum geometry and low-frequency optical conductivity of nodal planes