English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The incorporation of bismuth (Bi) in GaAs results in a large reduction of theband gap energy (E$_g$) accompanied with a large increase in the spin-orbitsplitting energy ($\bigtriangleup_{SO}$), leading to the condition that$\bigtriangleup_{SO} > E_g$ which is anticipated to reduce so-called CHSH Augerrecombination losses whereby the energy and momentum of a recombiningelectron-hole pair is given to a second hole which is excited into thespin-orbit band. We theoretically investigate the electronic structure ofexperimentally grown GaBi$_x$As$_{1-x}$ samples on (100) GaAs substrates bydirectly comparing our data with room temperature photo-modulated reflectance(PR) measurements. Our atomistic theoretical calculations, in agreement withthe PR measurements, confirm that E$_g$ is equal to $\bigtriangleup_{SO}$ for$\textit{x} \approx$ 9$%$. We then theoretically probe the inhomogeneousbroadening of the interband transition energies as a function of the alloydisorder. The broadening associated with spin-split-off transitions arises fromconventional alloy effects, while the behaviour of the heavy-hole transitionscan be well described using a valence band-anticrossing model. We show that forthe samples containing 8.5% and 10.4% Bi the difficulty in identifying a clearlight-hole-related transition energy from the measured PR data is due to thesignificant broadening of the host matrix light-hole states as a result of thepresence of a large number of Bi resonant states in the same energy range anddisorder in the alloy. We further provide quantitative estimates of the impactof supercell size and the assumed random distribution of Bi atoms on theinterband transition energies in GaBi$_{x}$As$_{1-x}$. Our calculations supporta type-I band alignment at the GaBi$_x$As$_{1-x}$/GaAs interface, consistentwith recent experimental findings.

Impact of alloy disorder on the band structure of compressively strained GaBiAs