First-principles study on the photoelectric properties of Lu-Eu co-doped β-Ga2O3
Wide band gap semiconductor β-Ga2O3 has become a research hotspot because of its excellent physi-cal and chemical properties.Based on the first-principle method of density functional theory,the band struc-tures,lattice constants and total energies of intrinsic β-Ga2O3,Lu-doped β-Ga2O3 at a doping concentration of 12.5 at％and Lu-Eu co-doped β-Ga2O3 at a doping concentration of 25 at％structures were calculated by GGA(Generalized Gradient Approximation)and GGA+U(Generalized Gradient Approximation-Hubbard U)methods in PBE(Perdew-Burke-Ernzerhof).It is found that the band gap calculated by the GGA+U method is closer to the experimental value,so the GGA+U method was used to calculate the basic physical properties,such as the density of states,dielectric function,absorption spectrum and reflectance,for the intrin-sic β-Ga2O3,Lu-doped β-Ga2O3 and Lu-Eu co-doped β-Ga2 O3 systems.The results show that the band gap of β-Ga2O3 is 4.24 eV,the band gap of Lu-doped β-Ga2O3 at a doping concentration of 12.5 at％is 2.23 eV,and the band gap of Lu-Eu co-doped β-Ga2O3 at a doping concentration of 25 at％is 0.9 eV.All of these are direct band gap semiconductors.The doping does not change the band gap mode of β-Ga2O3.The calculation results of optical properties show that the absorption coefficient and reflectance of Lu-doped β-Ga2O3 at a doping concentration of 12.5 at％and Lu-Eu co doped β-Ga2O3 at a doping concentration of 25 at％are stronger than those of intrinsic β-Ga2O3 in the low energy region.The absorption coefficient and reflec-tance of Lu-Eu-doped β-Ga2O3 are slightly stronger than Lu-doped β-Ga2O3,indicating that Lu-Eu co-doped β-Ga2O3 materials are likely to be used in the manufacture of infrared photoelectronic devices.
国家科技期刊平台
NSTL
万方数据
