Experimental and modelling study of InGaBiAs/InP alloys with up to 5.8% Bi, and with Δso > Eg

Chai, G. M.T. et al. (2015) Experimental and modelling study of InGaBiAs/InP alloys with up to 5.8% Bi, and with Δso > Eg. Semiconductor Science and Technology, 30, 094015. (doi: 10.1088/0268-1242/30/9/094015)

Abstract

Temperature dependent photo-modulated reflectance is used to measure the band gap Eg and spin–orbit splitting energy Δso in dilute-Bi In0.53Ga0.47As1-xBix/InP for 1.2% ≤ x ≤ 5.8%. At room temperature, Eg decreases with increasing Bi from 0.65 to 0.47 eV (∼2.6 μm), while Δso increases from 0.42 to 0.62 eV, leading to a crossover between Eg and Δso around 3.8% Bi. The 5.8% Bi sample is the first example of this alloy where Δso > Eg has been confirmed at all temperatures. The condition Δso > Eg is important for suppressing hot-hole-producing non-radiative Auger recombination and inter-valence band absorption losses and so holds promise for the development of mid-infra-red devices based on this material system. The measured variations of Eg and Δso as a function of Bi content at 300 K are compared to those calculated using a 12-band k.p Hamiltonian which includes valence band anti-crossing effects. The Eg results as a function of temperature are fitted with the Bose–Einstein model. We also look for evidence to support the prediction that Eg in dilute bismides may show a reduced temperature sensitivity, but find no clear indication of that.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Sweeney, Professor Stephen
• Authors: Chai, G. M.T., Broderick, C.A., O'Reilly, E.P., Othaman, Z., Jin, S.R., Petropoulos, J.P., Zhong, Y., Dongmo, P.B., Zide, J.M.O., Sweeney, S.J., and Hosea, T.J.C.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: Semiconductor Science and Technology
• Publisher: IOP Publishing
• ISSN: 0268-1242
• ISSN (Online): 1361-6641