Quasiparticle Lifetime in the Extrinsic Graphene and Graphene-Like Systems
Po-Hsin Shih1*, Ming-Fa Lin1, Feng-Lin Shyu2
1Department of Physics, National Cheng Kung University, Tainan, Taiwan
2Department of Physics, Republic of China Military Academy, Kaohsiung, Taiwan
* presenting author:Po-Hsin Shih, email:PHShih@phys.ncku.edu.tw
The random-phase approximation and Fermi golden rule are employed to study the many-body effects of monolayer graphene, silicene and germanene. The interband and intraband e-h excitations, and plasmon are included in the calculation of quasiparticle lifetime. Silicene and germanene exhibit more diversified low frequency coulomb excitations compared to graphene, mainly owing to the parabolic band and energy spacing at K point. In this work, we present the zero temperature coulomb decay rate which depends on the free carrier density and wave vector (or energy). These effects could reveal themselves in angle-resolved photoemission spectroscopy experiments.

Keywords: Lifetime, Graphene, Silicene, Germanene