High-temperature electron-hole liquid in diamond films

The ground state of the electron-hole liquid in diamond films is studied by density functional theory. The energy and equilibrium density of the liquid in films with thicknesses of a few nanometers are calculated. It is shown that the electron-hole liquid is multicomponent and consists of electrons and heavy, light, and spin-orbit split holes. The equilibrium density of electron-hole pairs in (111)-oriented diamond films is much higher than that in films with (100) orientation. The critical temperature of the electron-hole liquid in (111)-oriented diamond films is close to room temperature. [Display omitted] •Density functional theory is used to calculate the energy of a quasi-two-dimensional electron-hole liquid in diamond films.•The Kohn-Sham equations for electrons and heavy, light, and spin-orbit split holes are solved numerically.•The critical temperature of the electron-hole liquid in diamond films is close to room temperature.