No abstract

In this work we consider a quadron – a state of four carriers – two electrons and two holes in quantum dots with parabolic confinement. By using the Hatree-Fock method, the binding energies of the quadron and biexciton have been calculated for a full range of the electron-to-hole oscillator length ratio. The effect of the magnetic field on the binding energy of the quadron and biexciton has been also investigated. The crossing between anti-binding and binding in both the excited quadron and biexciton states for the certain ranges of the electron-to-hole oscillator length ratio has been found.

We theoretically study biexciton, exciton and charged excitons confined in 2D parabolic quantum dots in a magnetic field by using an unrestricted Hatree-Fork method. The energy and binding energy of exciton and biexciton are presented as a function of magnetic field which show their increase with increasing magnetic field, although small. Our results for the case of strong confinement in InAs/GaAs self-assembled quantum dots show that, while the binding energies of both exciton and negatively charged exciton are positive, the binding energies of the biexciton and positively charged exciton are negative indicating that biexcitons in this system are antibinding.