Midinfrared intersubband absorption in strain-compensated InGaP/InGaAs superlattices on (001) GaAs

Abstract

Intersubband optical transitions in strain-compensated In0.32Ga0.68As–In0.32Ga0.68P superlattices grown using gas-source molecular-beam epitaxy on (001)GaAs are investigated by means of midinfrared absorption and low-temperature photoluminescence. Strong absorption corresponding to the transition from the first to second electronic subband is measured at wavelengths between 5.6 and 10.5 μm. The data indicate that the conduction band offset between the strained In0.32Ga0.68As and the strained In0.32Ga0.68P is 370 meV and the electron effective mass in the strained In0.32Ga0.68As well is 0.060m0. This material system is an interesting GaAs-based candidate for applications in midinfrared intersubband emitters and detectors.

Energy and emission characteristics of superlattice quantum-cascade structures

“…The use of a sequence of narrow-and wide-gap InAs/AlSb-USHAKOV, MANAK based compounds allows one to increase the potentialbarrier height to ∆ E c ≈ 2 eV in the conduction band; such an increase is promising for developing shortwavelength quantum-cascade lasers in the range 2-5 µ m [22]. The structures based on InGaAs/InGaP layers grown on GaAs [23] and InGaAs/AlAs [24] substrates are also alternative compounds for short-wavelength quantum-cascade lasers.…”