We demonstrate a composite system consisting of a GaAs quantum well structure placed in the evanescent field of a fused silica microsphere and show evanescent coupling between excitons in the quantum well and high-Qwhispering gallery modes of the composite system. The composite system allows separate engineering of photonic and electronic confinement and can take advantage of high-Qfactor and small mode volume of fused silica microspheres. ©1998 American Institute of Physics.