Intrinsic carrier mobility of germanene is larger than graphene's: first-principle calculations

Abstract

Shown here is the intrinsic carrier mobility (ICM) of germanene, a group-IV graphene-like two-dimensional buckled nanosheet. Specifically, combining the Boltzmann transport equation with the relaxation time approximation at the first-principle level, it was calculated that the ICM of the germanene sheet can reach ∼6 × 10⁵ cm² V⁻¹ s⁻¹, in an order of magnitude (10⁵ cm² V⁻¹ s⁻¹), and even larger than that of graphene. The high ICM of germanene is attributed to the large buckled distance and the small effective mass. Since Ge has good compatibility with Si in the conventional semiconductor industry, the results indicate that germanene should be a good supplement to prospective nanoelectronics.