Abstract

Many exciton states in semiconductor nanocrystals have been attracting much interest recently from the viewpoint of optical nonlinearity and biexciton lasing. Here we have discovered for the first time the weakly correlated many exciton states in the weak confinement regime. These are not the ground state but the excited states of many excitons. For two exciton states, these have a large oscillator strength of transition from the exciton state, which increases almost in proportion to the volume of the nanocrystal in the large size regime and consequently make an important contribution to the optical nonlinearity.

© 1997 Optical Society of America