Conductivity and Resistivity of Dirac Electrons in Single-Component Molecular Conductor [Pd(dddt)_2]

Abstract

Dirac electrons, which have been found in the single-component molecular conductor [Pd(dddt)_2] under pressure, are examined by calculating the conductivity and resistivity in terms of a tight-binding model for several pressures of P GPa, which give a nodal line semimetal or insulator. The temperature (T) dependence of the conductivity shows that the conductivity increases linearly under pressure at low T due to the Dirac cone but stays almost constant at high T. Further, at lower pressures, the conductivity is suppressed due to an unconventional gap, which is examined by calculating the resistivity. The resistivity exhibits a pseudogap-like behavior even in the case described by the Dirac cone. Such behavior originates from a novel role of the nodal line semimetal followed by a pseudogap that is different from a band gap. The present result reasonably explains the resistivity observed in the experiment.

16 pages, 7 figures

References in corpus (3)

• Phase transition between the quantum spin Hall and insulator phases in 3D: emergence of a topological gapless phase
• Anisotropic Conductivity of Nodal Line Semimetal in Single-Component Molecular Conductor [Pd(dddt)${}_2$]
• Analysis of Dirac Point in the Organic Conductor $\alpha$-(BEDT-TTF)${}_2$I${}_3$

Cited by in corpus (9)

• Effective Hamiltonian of Topological Nodal Line Semimetal in Single-Component Molecular Conductor [Pd(dddt)${}_2$] from First-Principles
• Electronic Structure of a Single-Component Molecular Conductor [Pd(dddt)${}_2$] (dddt = 5,6-dihydro-1,4-dithiin-2,3-dithiolate) under High Pressure
• Berry Phase of Dirac Nodal Line Semimetal in Single-Component Molecular Conductor
• Role of Velocity Field and Principal Axis of Tilted Dirac Cones in Effective Hamlitonan of Non-Coplanar Nodal Loop
• Tight-Binding Model and Electronic Property of Dirac Nodal Line in Single-Component Molecular Conductor [Pt(dmdt)${}_2$]
• Anomalous conductivity of two-dimensional Dirac electrons in organic conductor under pressures
• Electric Transport of Nodal Line Semimetal in Single-Component Molecular Conductor
• Possible Spin-Density Wave on Fermi Arc of Edge State in Single-Component Molecular Conductors [Pt(dmdt)${}_2$] and [Ni(dmdt)${}_2$]
• Fragment-orbital-dependent spin fluctuations in the single-component molecular conductor [Ni(dmdt)${}_2$]