Theoretical study of exciton Mott transition in quantum wells through interband transition energy of excitons

The effect of confinement potential on Exciton Mott Transition (EMT) has been numerically studied through interband transition energy (IBTE) of excitons confined in QW. The influence of confinement profile is estimated by adding square, parabolic and triangular potentials using variation technique adjoined with effective mass approximation. The effect of confinement profile, barrier height and well width on binding energy and IBTE has been obtained by optimizing the Hamiltonian at ground state by tuning direct exciton (DX) concentration. The screening effects of optically pumped DXs is accounted through Thomas-Fermi dielectric screening. Further, it is found that BE of exciton vanishes at a critical concentration (nc ∼1017cm−3) to demonstrate EMT. However, the onset of the transition is at 1015 cm−3 and completed at 1018 cm−3. The results are observed irrespective of the confinements and other material parameters. A basic bandgap renormalization process in the EMT is observed due to overlapping of charge clouds. It is also confirmed that TF dielectric screening effectively accounts the EMT in nanostructures.