Resonance Raman scattering studies of composition-modulated GaP/InP short-period superlattices

Abstract

Resonance Raman scattering and electroreflection measurements on laterally composition modulated GaP/ InP short-period superlattices are presented. The electroreflectance spectra give the fundamental band-gap energy of the lateral superlattice at 1.69Ϯ0.05 eV, which is about 210 meV lower than the band-gap energy of a GaInP random alloy with the same overall composition. In resonance Raman spectra measured with the polarization of both excitation and scattered photons along the composition modulation direction, the GaP-like longitudinal optical phonon redshifts by 4.0Ϯ0.5 cm Ϫ1 near the resonance with the fundamental energy gap. A comparison of the experimental data with a model calculation gives the average In composition in the In-rich region as 0.70Ϯ0.02, and the average Ga composition in the Ga-rich region as 0.68Ϯ0.02.

Temperature dependent polarization switching and band-gap anomalies in strained GaxIn1−xAs quantum wire heterostructures

“…15 Also depending on the degree of lateral composition modulation, the indium composition of the alternating Ga-and In-rich QWRs can be as much as 30% and 70%, respectively. 16 QWR heights are controlled in the same way as QWs, and they vary from 75 to 100 Å. Moreover, ͑GaAs͒ m /͑InAs͒ n SPSs on InP typically result in QWRs that display the temperature stable PL discussed above.…”

Linear and second-order optical response of III-V monolayer superlattices

“…14 InP/GaP, being one of the material combinations which spontaneously constructs the SL under specific conditions, has been subject to numerous experimental works 15,16,17 including cathodoluminescence experiments 18,19,20 and studies on the influence of pressure, SL period and barrier thickness 21,22,23 on the optical transitions. Likewise GaAs/GaP 24,25 and GaAs/AlAs 26,27,28,29,30,31,32 have also been extensively investigated in the past.…”

Unveiling interfaces between In-rich and Ga-rich GaInP vertical slabs of laterally composition modulated structures

“…The polarization anisotropy is a direct result of the LCM structure. 21) Furthermore, the CER spectrum shifted towards a lower energy as the V=III ratio decreased, as in the case of the PL spectrum shown in Fig. 2.…”