Theoretical study on electronic properties of p-type GaN nanowire surface covered with Cs

摘要: By using density functional theory, we have investigated the Cs adsorption mechanism of Mg-doped GaN nanowire photocathode. The results show that in nanowire, Mg atoms tend to replace Ga central position, because position has lowest formation energy, and carrier concentration is highest, which shows better conductivity. Besides, doping leads Fermi level close valence band, exhibiting p-type After activation, most stable site nanowires B N site. adsorption, conduction band minimum maximum both move lower favorable for forming n-type surface state improving photoelectron escape probability. This study can be used guide process nanowires, helpful improve performance nanowire-based optoelectronic devices.