Interplay between electron-hole and impurity scattering in HgTe-based quantum wells

A 20-nm-wide (100)-oriented HgTe quantum well (QW) hosts a two-dimensional (2D) semimetal comprising both electrons and holes. In this study, we report that in addition to the previously observed quadratic temperature dependence of resistance, the system also displays an unexpected linear temperature dependence within specific top-gate voltage ranges. To account for this behavior, we extend the existing theoretical framework for temperature-dependent resistance in HgTe QW-based 2D semimetals with a focus on electron-hole scattering at low temperatures. Using the Boltzmann transport equation, we investigate the role of electron-hole interactions in this 2D semimetal. Our calculations reproduce a resistivity temperature dependence that aligns closely with experimental data. These findings establish this system as a robust platform for exploring interaction-limited transport regimes in a two-component plasma, particularly in the presence of disorder.