Calculations of the local electronic structure of a single isoelectronic impurity: boron in gallium arsenide

The ability to change the band gap and electronic structure with very low doping levels of isoelectronic atoms has led to extensive study of highly mismatched alloys (HMAs) of III-V materials based on nitrides, such as GaAsN in the last few decades [1]. However, HMAs with different group III elements such as BGaAs, which could be used in Si based devices [2], continue to be less investigated. Based on multiband tight-binding Green’s function calculations, successfully used in the past [3] for single isoelectronic atoms in HMAs, here we calculate the local density of states (LDOS) for a single B dopant in GaAs. Comparing with X-STM measurements [4], the LDOS are analyzed as function of the energy and position. The results confirm a principal anion-like contribution to the LDOS and discuss the energy position at which the LDOS peak from the dopant emerges. These results are compared with previous results for N in GaAs, which has a cation-like contribution to the LDOS, highlighting the differences between the two systems.

[1] W. Walukiewicz and J. M. Zide, Journal of Applied Physics 127, 010401 (2020).

[2] P. Rodriguez, L. Auvray, H. Dumont, J. Dazord, and Y. Monteil, Journal of crystal growth 298, 81 (2007).

[3] C. M. Krammel, A. R. da Cruz, M. E. Flatté, M. Roy, P. A. Maksym, L. Y. Zhang, K. Wang, Y. Y. Li, S. M. Wang, and P. M. Koenraad, Phys. Rev. B 101, 024113 (2020).

[4] C. M. Krammel, ISBN: 978-90-386-4414-1 (2018).