Optical and structural investigation of InAs/AlSb/GaSb heterostructures (original) (raw)
We report on the growth and characterisation of non-intentionally doped InAs/AlSb strained multiple quantum wells (MQWs), grown on GaSb substrates by molecular beam epitaxy (MBE). The structural characterisation is performed using X-ray re¯ectometry (XRR) as a complementary tool to high resolution X-ray diraction (HRXRD) experiments. For the ®rst time in this material system, optical characterisation by photo-induced absorption spectroscopy have been carried out. A strong e 1 3 e 2 p-polarised intersubband absorption is observed with a full width at half maximum of 11 meV at 77 K, showing the good quality of the material. Ó
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