Competition between excitonic gap generation and disorder scattering in graphene

Abstract

We study the disorder effect on the excitonic gap generation caused by strong Coulomb interaction in graphene. By solving the self-consistently coupled equations of dynamical fermion gap $m$ and disorder scattering rate $\Gamma$, we found a critical line on the plane of interaction strength $\lambda$ and disorder strength $g$. The phase diagram is divided into two regions: in the region with large $\lambda$ and small $g$, $m\ne 0$ and $\Gamma =0$; in the other region, $m=0$ and $\Gamma \ne 0$ for nonzero $g$. In particular, there is no coexistence of finite fermion gap and finite scattering rate. These results imply a strong competition between excitonic gap generation and disorder scattering. This conclusion does not change when an additional contact four-fermion interaction is included. For sufficiently large $\lambda$, the growing disorder may drive a quantum phase transition from an excitonic insulator to a metal.

8 pages, 1 figure

References in corpus (29)

• The electronic properties of graphene
• Charged Impurity Scattering in Graphene
• Properties of Graphene: A Theoretical Perspective
• Measurement of Scattering Rate and Minimum Conductivity in Graphene
• Colloquium: The transport properties of graphene: An introduction
• Gauge fields in graphene
• Metallic behavior and related phenomena in two dimensions
• Defect scattering in graphene
• Non-Fermi liquid behaviour of electrons in the half-filled honeycomb lattice (A renormalization group approach)
• Interactions and phase transitions on graphene's honeycomb lattice
• Electron transport in disordered graphene
• Magnetic field driven metal-insulator phase transition in planar systems
• Effect of Disorder on Transport in Graphene
• Ghost excitonic insulator transition in layered graphite
• Is graphene in vacuum an insulator?
• Impurity-Induced Quasiparticle Transport and Universal Limit Wiedemann-Franz Violation in d-Wave Superconductors
• Quantum critical scaling in graphene
• Coulomb interaction, ripples, and the minimal conductivity of graphene
• Lattice field theory simulations of graphene
• Effect of electron-electron interactions on the conductivity of clean graphene
• Low energy theory of disordered graphene
• Disorder and Electronic Transport in Graphene
• Quantum Critical Behaviour in a Graphene-like Model
• Excitonic instability in two-dimensional degenerate semimetals
• Gap generation and semimetal-insulator phase transition in graphene
• Minimal conductivity in graphene: interaction corrections and ultraviolet anomaly
• Conductivity of interacting massless Dirac particles in graphene: Collisionless regime
• Interaction and excitonic insulating transition in graphene
• Coulomb interacting Dirac fermions in disordered graphene

Cited by in corpus (9)

• Disorder effects at a nematic quantum critical point in d-wave cuprate superconductor
• Excitonic pairing and insulating transition in two-dimensional semi-Dirac semimetals
• Influence of Coulomb interaction on the anisotropic Dirac cone in graphene
• Eliashberg theory of excitonic insulating transition in graphene
• Superconductivity in two-dimensional disordered Dirac semimetals
• Dynamical gap generation in 2D Dirac semimetal with deformed Dirac cone
• Robustness of the semimetal state of Na3Bi and Cd3As2 against Coulomb interaction
• Quantum critical phenomena of the excitonic insulating transition in two dimensions
• Reduced QED with few planes and fermion gap generation