Probing quantum coherent states in bilayer graphene

Article

Abstract

An active area of post-CMOS device research is to study the possibility of realizing and exploiting exotic quantum states in nanostructures. In this paper we consider one such system, two layers of graphene separated by an oxide insulator. This system has been predicted to have an excitonic condensate that survives above room temperature. We describe a computational technique—path integral quantum Monte Carlo (PIMC)—that directly simulates many-body quantum phenomena, including excitonic condensation. Starting from a simplified quasiparticle model, the many-body PIMC simulations show excitonic pairing and a confirm a superfluid phase that persists above room temperature. We then present an atomistic PIMC model that captures more details of graphene than our quasiparticle model, and discuss how to extract parameters for a non-equilibrium Green’s function calculation.

Keywords

Graphene Exciton condensate Path integral Quantum Monte Carlo Superfluidity 

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Copyright information

© Springer Science+Business Media LLC 2009

Authors and Affiliations

  1. 1.Department of Electrical and Computer Engineering, Micro and Nanotechnology Laboratory, Institute for Cond. Mat. TheoryUniversity of Illinois at Urbana-ChampaignUrbanaUSA
  2. 2.Department of PhysicsArizona State UniversityTempeUSA

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