Plasmon-phonon gain in CdHgTe structures with near-surface HgTe quantum wells

The work is devoted to the study of plasmon–phonon gain in CdHgTe/HgTe structures with quantum wells (QWs) located near the boundary of the structure with vacuum/air (near-surface QWs). The issue of the influence of the distance between QWs on the plasmon–phonon gain has been studied. It has been shown that a decrease in the distance from the nearest QW to the structure boundary leads to an increase in the phase velocity of the generated plasmon–phonon and a decrease in the power absorbed by phonons in the barriers. This leads to a decrease in the threshold concentration of nonequilibrium carriers required to begin of plasmon–phonon gain under conditions of optical excitation.