Our group carries out wide ranging mid-infrared research programmes involving fundamental investigations, device development and applications of mid-infrared quantum cascade lasers. Our main efforts are concentrated at the 3-4 μm wavelength range which is of key technological importance for a wide range of applications. Many important hydrocarbon species, for example ethane, methane, acetone, formaldehyde and butane have their strongest absorption features in this region. This leads to many potential applications in areas such as clinical diagnostics, process monitoring, control of outdoor and indoor pollution, and remote detection of oil and gas deposits. First demonstration in 2004 and successful development of short wavelength InGaAs/AlAsSb/InP based quantum cascade lasers were achieved at Sheffield.
It was our group, which in 2003 demonstrated the first InGaAs/InAlAs and GaAs/AlGaAs quantum cascade lasers grown by metal-organic vapour phase epitaxy (MOVPE) a technique which has high potential advantages over molecular beam epitaxy. This achievement results in MOVPE becoming widely used for the growth of these lasers by many world leading research and industrial groups.
Related research areas: