High-temperature electron-hole liquid in diamond films

Stability of electron–hole liquid in quantum wells

“…Besides transition metal dichalcogenides, an interesting platform for the studies of EHL is offered by layered semiconductors InSe, GaS, and GaSe. Thus, the exciton binding energy in GaS is about 100 meV [22], and one can anticipate an EHL critical temperature in GaS layers of about 230 K. We also note that the formation of an EHL with a critical temperature close to room temperature is possible in nanometer-thick diamond films [15].…”

“…Below, we use the excitonic system of units, i.e., length and energy are measured in the units of exciton Bohr radius a ex = ε 2 /μe 2 and exciton Rydberg Ry ex = e 2 / 2εa ex , respectively (here, ε is the dielectric constant, μ = m e m h /(m e + m h ) is the reduced mass, and m e and m h are the electron and hole masses, respectively). To calculate the EHL energy, we use the model put forward in [14,15]. In the framework of density functional theory, the total energy of electrons and two types of holes is written as…”

“…In recent studies [13][14][15], density functional theory was used to calculate the EHL energy and find the equilibrium density of electron-hole pairs in quantum wells. The calculation results for SiO 2 /Si and Si/SiGe quantum wells [13,14] are in good agreement with experimental data [4][5][6][7][8].…”