The influence of N and Bi on the band structure and band offsets of InAsNBi alloys

¹ Tech X Academy, Shenzhen Polytechnic University, Shenzhen, 518055, China
² Institute of Telecommunication and Navigation Satellites, CAST, Beijing, 100094, China

^a zhangcheng4@126.com
^b 13439757136@139.com
^c* Corresponding author: dyi0206@szpu.edu.cn

Abstract

We present the electronic properties of InAsNBi with N and Bi concentrations based on 16×16 band Hamiltonian model. This model is extended from Band Anti-crossing (BAC) and the dimension of basis states used in the Hamiltonian matrix is 16. Under the condition that the quaternary compound matches the lattice configuration of the InAs substrate, the variations of band gap (E_g), spin-orbit coupling energy (Δ_SO) has been examined as a dependency on the mole fractions of N and Bi. Our findings indicate the integration of N and Bi atoms in InAs gives rise to a substantial band gap energy minimization and the growth of spin-orbit coupling energy. Subsequently a crossover (Δ_SO = E_g) is observed at a Bi concentration of 0.37%, which contributes to enhancing the effectiveness of photonic devices by suppress Auger recombination. We further reveal the band offset with different N and Bi concentrations and considered the influence of the substrate on the material deviation. The conduction band energy mislignment (ΔE_c) of InAsNBi exceeds energy misalignment in the valence bands (ΔE_v), which is required to improve thermal-insensitive characteristics of semiconductor devices. Moreover, the significant mastery over the edges of the conduction and valence bands by adjusting the concentration of N and Bi will increase the flexibility to design InAsNBi/InAs structures.