In this work we investigate the influence of extractor design and temperature on transport properties of quantum
cascade detector. For this purpose we realize numerical calculation of electron lifetimes considering electronphonon
and electron impurities scattering. Electron-phonon interactions are treated using Fermi Golden Rule
which allows to calculate lifetime of carriers with temperature and structure design taking into account. Transport
characteristics of the quantum cascade detectors have been computed using density matrix theory. As a result, we
have obtained the system of ordinary differential equations describing dynamics of electron distribution functions
and intersubband correlations. Managing carrier lifetime in quantum wells gives us possibility to control quantum
efficiency and response.
A new possible method of frequency tuning of the distributed feedback laser (DFB) based on cholesteric liquid crystals (CLC) is investigated. In this method the active media is irradiated with UV light to stimulate photo-transformation of the molecules of chiral dopant. This transformation changes twisting power of chiral dopant and, as results, the position of the reflection band of CLC. Based on this principle, fluent and reversable frequency tuning of the lasing irradiation of DFB-laser is realized.