Creation of quasiparticles in graphene by a time-dependent electric field

摘要: We investigate the creation of massless quasiparticle pairs from vacuum state in graphene by space homogeneous time-dependent electric field. For this purpose formalism ($2+1$)-dimensional quantum electrodynamics is applied to case a nonstationary background with arbitrary time dependence allowing $S$-matrix formulation problem. The number created per unit area expressed via asymptotic solution at $t\ensuremath{\rightarrow}\ensuremath{\infty}$ second-order differential equation an oscillator-type complex frequency satisfying some initial conditions $t\ensuremath{\rightarrow}\ensuremath{-}\ensuremath{\infty}$. obtained results are field specific on admitting exact Dirac equation. calculated analytically wide variety different regimes depending parameters investigated earlier static reproduced as particular our formalism. It shown that rate often larger than