Optical nonlinearity induced by exciton-biexciton coherent effects in InGaAs quantum dots
Hideki Gotoh, Hidehiko Kamada, Hidetoshi Nakano +3 more
We report on large optical nonlinear effects induced by coherent interactions between excitons and biexcitons in quantum dots. The absorption spectra in an exciton–biexciton system are measured in InGaAs quantum dots by using single dot spectroscopy. The spectra exhibit unusual shapes that have a transparent region under a strong excitation condition. A pump–probe measurement ensures that the exciton state is erased by a quantum interference effect with exciton and biexciton photoabsorption processes. These results suggest that optical functions such as electromagnetically induced transparency are feasible with excitons and biexcitons in quantum dots.
Applied Physics Letters•Aug 26, 2005•7 citations