the effect of exchange-correlation holes on the temperature dependent dynamic dielectric function of single-layer quantum wells and coupled nanolayers

in this paper, for the first time we have studied theoretically the effect of exchange-correlation holes around electrons in gaalas/gaas/gaalas nanostructure on the temperature-dependent dynamic dielectric function of two-dimensional electron gas by employing random phase, stls and hubbard approximations. also, we have investigated another interesting system which is coupled quantum wells structure. to make a good comparison and show the effect of local field, the numerical results have been compared with those obtained within rpa which considers long-range interactions and ignores exchange-correlation effects completely. we found that taking into account the exchange-correlation effects changes considerably the values of dynamic dielectric function at low electron densities at finite temperatures.