Experimental results on the manufacturing and study of the properties of 7-8 μm wavelength range injection quantum-cascade lasers (QCLs) with a waveguide with a thin top cladding layer based on indium phosphide are presented. The heterostructure is formed by molecular beam epitaxy on an InP substrate, with a In0.53Ga0.47As/Al0.48In0.52As active region. Lasing at a wavelength of 7.8 μm at a temperature of 300 K with a threshold current density of ~ 6 kA / cm2 is obtained. Characteristic temperature T0 and T1 values for the QCLs are about 150 K and 450 K, respectively. Obtained results confirm the promising design of the QCLs with a waveguide with a thin top cladding layer for detecting liquids and microfluidic devices development.

The generation of radiation in 7-8 μm spectral range quantum-cascade lasers with the design of the active region based on a two-phonon resonance design is demonstrated. The wavelength of radiation tuning range under the action of the control voltage was 35 cm-1. The heterostructure of a quantum-cascade laser was grown by molecular beam epitaxy based on a In0.53Ga0.47As/Al0.48In0.52As heteropair, matched by lattice parameter with an InP substrate, and InP layers, which functioned as waveguide claddings.