Dephasing Time in Graphene Due to Interaction with Flexural Phonons

Abstract

We investigate decoherence of an electron in graphene caused by electron-flexural phonon interaction. We find out that flexural phonons can produce a dephasing rate comparable to the electron-electron one. The problem appears to be quite special because there is a large interval of temperature where the dephasing induced by phonons cannot be obtained using the golden rule. We evaluate this rate for a wide range of density (n) and temperature (T) and determine several asymptotic regions with the temperature dependence crossing over from τ_{ϕ}^{-1}∼T^{2} to τ_{ϕ}^{-1}∼T when temperature increases. We also find τ_{ϕ}^{-1} to be a nonmonotonic function of n. These distinctive features of the new contribution can provide an effective way to identify flexural phonons in graphene through the electronic transport by measuring the weak-localization corrections in magnetoresistance.