Inversion Symmetry and Wave-Function-Nodal-Lines of Dirac Electrons in Organic Conductor alpha-(BEDT-TTF)_2I_3

Abstract

By examining organic conductor alpha-(BEDT-TTF)_2I_3 which is described by a nearest neighbors tight-binding model it is shown that because of inversion symmetry, each component of a wave function (WF) exhibits nodal lines (NLs) in the Brillouin zone. In the absence of any band crossing, each NL connects two time reversal invariant momenta (TRIM) as partners. In the presence of a pair of Dirac points (band crossing), for each band that crosses and for each WF component there is a NL that connects the pair of Dirac points via a TRIM without partner. This second kind of NL leads to a discontinuous sign change for non vanishing components of the WF. Such a property is at the origin of the +/- pi Berry phase accumulated on a contour integral encircling one Dirac point. The results are examplified by numerical calculation of WFs components for the above conductor with a 3/4 filled band.

4 pages, 3 figs

References in corpus (5)

• Topological Insulators with Inversion Symmetry
• The Zak phase and the existence of edge states in graphene
• Electronic Properties Close to Dirac Cone in Two-Dimensional Organic Conductor $\alpha$-(BEDT-TTF)${}_2$I${}_3$
• Berry Curvature of the Dirac Particle in $\alpha$-(BEDT-TTF)${}_2$I${}_3$
• Effects of Zeroline and Ferrimagnetic Fluctuation on Nuclear Magnetic Resonance for Dirac Electrons in Molecular Conductor alpha-(BEDT-TTF)2I3

Cited by in corpus (4)

• Correlation Effects on Charge Order and Zero-Gap State in the Organic Conductor α-(BEDT-TTF)2I3
• Exotic Dirac Cones on the Band Structure of $\alpha$-STF${}_2$I${}_3$ at Ambient Temperature and Pressure
• Electronic Structure of a Single-Component Molecular Conductor [Pd(dddt)${}_2$] (dddt = 5,6-dihydro-1,4-dithiin-2,3-dithiolate) under High Pressure
• Analysis of Dirac Point in the Organic Conductor $\alpha$-(BEDT-TTF)${}_2$I${}_3$