Optimization of terahertz absorption in periodic quantum well structures

In this work, the linear absorption spectra for periodic arrays of GaAs-GaAsAl quantum wells with different thicknesses, inside electromagnetic wave has been studied. The eigen energies and eigen functions are calculated by solving the Schr\"odinger equation numerically. The absorption spectra are obtained using the density matrix approach and the effects of quantum well parameters have been studied. Results show that for a wide range of parameters the absorption peaks lie in the terahertz region. Furthermore, it is possible to adjust the frequency of absorption peak in the terahertz range by changing the width and height of the wells or array numbers that could be used in terahertz devices.