Effect of electron-electron interactions on a two-dimensional electron gas in II-VI ${\mathrm{ZnS}}_{0.06}{\mathrm{Se}}_{0.94}{/\mathrm{Z}\mathrm{n}}_{0.8}{\mathrm{Cd}}_{0.2}\mathrm{Se}$ quantum wells

A magnetotransport study has been performed in II-VI ${\mathrm{ZnS}}_{0.06}{\mathrm{Se}}_{0.94}{/\mathrm{Z}\mathrm{n}}_{0.8}{\mathrm{Cd}}_{0.2}\mathrm{Se}$ quantum wells. We observed the quantum effects of weak localization and electron-electron interactions on the two-dimensional electron gas in the ${\mathrm{Zn}}_{0.8}{\mathrm{Cd}}_{0.2}\mathrm{Se}$ well. The effective mass of electrons in this highly correlated system, determined from Shubnikov–de Haas measurements, exhibits a strong magnetic field dependence: $m^{*}{/m}_0{=0.143+0.0027B}^2.$ The mass enhancement is attributed to the “dressing” of electrons by the many-particle effect due to electron-electron interactions.