Investigation of the anisotropic electron g factor as a probe of the electronic structure of GaBi${}_x$As${}_{1-x}$/GaAs epilayers

Abstract

The electron Landé g factor ($g^{\ast }$) is investigated both experimentally and theoretically in a series of GaBi${}_x$As${}_{1-x}$/GaAs strained epitaxial layers, for bismuth compositions up to $x=3.8$%. We measure $g^{\ast }$ via time-resolved photoluminescence spectroscopy, which we use to analyze the spin quantum beats in the polarization of the photoluminescence in the presence of an externally applied magnetic field. The experimental measurements are compared directly to atomistic tight-binding calculations on large supercells, which allows us to explicitly account for alloy disorder effects. We demonstrate that the magnitude of $g^{\ast }$ increases strongly with increasing Bi composition $x$ and, based on the agreement between the theoretical calculations and experimental measurements, elucidate the underlying causes of the observed variation of $g^{\ast }$. By performing measurements in which the orientation of the applied magnetic field is changed, we further demonstrate that $g^{\ast }$ is strongly anisotropic. We quantify the observed variation of $g^{\ast }$ with $x$, and its anisotropy, in terms of a combination of epitaxial strain and Bi-induced hybridization of valence states due to alloy disorder, which strongly perturbs the electronic structure.

References in corpus (4)

• Impact of alloy disorder on the band structure of compressively strained GaBiAs
• Temperature dependence of the electron spin g factor in GaAs
• Electron spin relaxation in GaAs${}_{1-x}$Bi${}_x$: Effects of spin-orbit tuning by Bi incorporation
• Atomistic tight-binding study of electronic structure and interband optical transitions in GaBi${}_x$As${}_{1-x}$/GaAs quantum wells

Cited by in corpus (6)

• Impact of disorder on the optoelectronic properties of GaN${}_y$As${}_{1-x-y}$Bi${}_x$ alloys and heterostructures
• Electronic structure evolution in dilute carbide Ge${}_{1-x}$C${}_x$ alloys and implications for device applications
• Large-scale atomistic simulations demonstrate dominant alloy disorder effects in GaBi${}_x$As${}_{1-x}$/GaAs multiple quantum wells
• Towards low-loss telecom-wavelength photonic devices by designing GaBi${}_x$As${}_{1-x}$/GaAs core$-$shell nanowires
• Tunable band-gap and isotropic light absorption from bismuth-containing GaAs core$-$shell and multi$-$shell nanowires
• Atomistic tight binding study of quantum confined Stark effect in GaBi${}_x$As${}_{1-x}$/GaAs quantum wells