The dispersion laws of two-dimensional plasmons in narrow-gap HgTe/CdHgTe quantum wells are calculated taking into account the spatial dispersion of the electron susceptibility. At the energy scale of the band gap the dependence of plasmon frequencies on the wave vector is shown to be close to linear that changes significantly the critical concentration of noneqilibrium electron-hole gas corresponding to ‘switching-on’ the carrier recombination with plasmon emission. The recombination rates with the plasmon emission have been calculated. The ‘plasmon’ recombination is shown to dominate at the carrier concentration over (1.2–2) 10¹¹ cm⁻² in a 5-nm-wide HgTe quantum well (band gap of 35 meV) that makes plasmon generation (spasing) in THz frequency range feasible.

考虑到电子敏感性的空间色散，计算了窄间隙HgTe / CdHgTe量子阱中二维等离激元的色散规律。在带隙的能级上，等离激元频率对波矢量的依赖性接近线性，这显着改变了非平衡电子空穴气体的临界浓度，这与“开启”载流子重组与等离激元发射相对应。已计算出具有等离子体激元发射的重组率。显示在5 nm宽的HgTe量子阱（带隙为35 meV）中，当载流子浓度超过（1.2–2）10 ¹¹ cm ^-2时，“等离激元”重组占主导地位，从而在THz中产生等离激元。频率范围可行。