MOVPE grown quantum cascade lasers

We report the metal-organic vapour phase epitaxy growth of quantum cascade lasers (QCLs) in both the GaAs–AlGaAs and InGaAs–AlInAs–InP materials systems. The GaAs based sample shows an increased emission wavelength relative to an equivalent design grown by molecular beam epitaxy, which we attribute to interfacial grading in the metal-organic vapour phase epitaxy device. The InP-based QCL View the MathML source operates in pulsed mode at room temperature, with low temperature threshold current density View the MathML source. This performance is comparable with that previously reported for similar structures grown by molecular beam epitaxy. The high quality interfaces necessary for successful QCL operation are achieved by using individually purged vent/run valves in the gas-handling section of the reactor, as well as a low growth rate for the active region of the structure.