Structural parameters governing properties of GaInSb/InAs infra-red detectors

Models of GaSb/InAs type-II infrared detectors at very long wavelengths: band offsets and interface bonds

“…By employing the models and techniques described in section 2, we have carried out a series of studies on the absorption of VLWIR radiation in GaSb/InAs superlattices with proposed applications as photodetectors. In the first instance, we present an appraisal of the success of our techniques in modelling these III-V structures, which have proved to be successful for a large range of systems in the past [12,18,19,21,22]. This investigation, which is reported in section 3.1, was carried out by calculating the absorption coefficient for a series of structures nominally identical to some recently fabricated [9] for IR photodetectors and comparing our results with the available experimental data.…”

Improved tight-binding parameters of III–V semiconductor alloys and their application to type-II superlattices

“…The calculated band-gap energies agree well with the experimental ones except for the (InAs) 18 (Ga 0.75 In 0.25 Sb) 8 , which has the thickest InAs layers in the present structures. In the (InAs) 18 (Ga 0.75 In 0.25 Sb) 8 T2SL, the difference of the experimental E g from the calculation results of the TB5 and an empirical pseudopotential method (EPM), 24) which we show in Table VI, may be attributed to the interface quality of the heterojunctions since the interface states become sensitive to the growth conditions due to the locally increased tensile strain in the thicker InAs layers. 34) Next, to check the E k  relation near the band edges obtained by the TB5, we have calculated the optical absorption spectrum of the T2SL based on the Fermi golden rule (same method as in Ref.…”

“…), E g (ETBM), and E g (EPM) denote the band-gap energies obtained from the experiment, the calculations of TB5 method and the empirical pseudopotential method, respectively; we had read E g (EPM) from the rising edge of the calculated absorption spectrum in Ref. 24 T2SL calculated with TB5 and EPM scheme. 24) HH1 (LH1)-C1 stands for the transition between the sub-band of the first heavy (light)-hole to the first conduction sub-band, respectively; HH1-C2 denotes the transition of the first heavy-hole sub-band to the second conduction sub-band.…”

“…24 T2SL calculated with TB5 and EPM scheme. 24) HH1 (LH1)-C1 stands for the transition between the sub-band of the first heavy (light)-hole to the first conduction sub-band, respectively; HH1-C2 denotes the transition of the first heavy-hole sub-band to the second conduction sub-band. The arrows indicate the energy difference between the band edges for each band-to-band transition.…”

“…18,19) T2SLs including alloy layers such as (InAs)/(Ga x In 1−x Sb) are also proposed to achieve narrower gaps for the very long wave-length infrared detection. [20][21][22][23][24] As far as we know, there is no report on a TB calculation of the electronic structure of a T2SL containing a ternary alloy. In this paper, we present applications of the TB method to (InAs)/(Ga x In 1−x Sb) T2SLs, viz, the calculation results of these band gaps and an optical absorption spectrum of the T2SL.…”