▎ 摘　　要

We calculated electron-impurity scattering rate ((h) over bar/tau) as a function of quasiparticle energy (epsilon) for doped single layer graphene (SLG), bilayer graphene (BLG) and two-dimensional electron gas (2DEG) at zero temperature. ((h) over bar/tau) of SLG has been computed analytically as well as numerically. Computed results show that (h) over bar/tau of SLG; (a) tends to zero at epsilon = 0 and, (b) it exhibits peak at approximate to 1.6 epsilon(f), where epsilon(f) is Fermi energy. Contrary to this, (h) over bar/tau of 2DEG and BLG show their maximum values at epsilon = 0 and decline thereafter on increasing epsilon to attain a minimum at around epsilon equal to Fermi energy. We thus find that (h) over bar/tau versus epsilon of SLG displays an entirely different behavior than that of BLG and 2DEG, suggesting that electron-impurity scattering process in SLG sharply differs from those in BLG and 2DEG. Further, computed (h) over bar/tau of SLG exhibits a large variation in its magnitude over the energy range of 0