Optical conductivity of triple point fermions. (12th January 2021)

• Record Type: Journal Article
• Authors: Habibi, Alireza; Farajollahpour, Tohid; Jafari, S A
• Is Part Of: Journal of physics. Volume 33:Number 12(2021)
• Publication Date: 2021-01-12
• Subjects: triple point fermion -- topological insulator -- three-fold degeneracy -- optical conductivity -- Chern number -- flat band; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/abd739
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: As a low-energy effective theory on non-symmorphic lattices, we consider a generic triple point fermion Hamiltonian, which is parameterized by an angular parameter λ . We find strong λ dependence in both Drude and interband optical absorption of these systems. The deviation of the T 2 coefficient of the Drude weight from Dirac/Weyl fermions can be used as a quick way to optically distinguish the triple point degeneracies from the Dirac/Weyl degeneracies. At the particular λ = π /6 point, we find that the 'helicity' reversal optical transition matrix element is identically zero. Nevertheless, deviating from this point, the helicity reversal emerges as an absorption channel.