Oscillator strength dependence of cavity-polariton mode splitting in semiconductor microcavities

We demonstrate the continuous alteration of the exciton-polariton mode splitting in semiconductor microcavities, through the change of the exciton oscillator strength induced by quantum confined Stark effect (QCSE). This is clear evidence of the direct influence of the oscillator strength on the mode splitting. A wide range variation, from 0 to 2 nm, of the splitting is obtained by the tuning of the cavity resonance based on the in-plane dispersion of the photon mode as well as the tuning of exciton energy by QCSE. The influence of the field-induced exciton line broadening on the mode splitting is also observed for the applied electric field as high as 90 kV/cm.