Radiative lifetime of exciton polaritons in distributed feedback cavity

Radiative lifetime of periodically arranged luminescent rods in a waveguide structure is measured with an optical Kerr gate technique. The period of t he structure was chosen to be around twice of the wavelength of the exciton luminescence. The rods are made of (C6H5C2H4NH3)(2)PbI4, which has a large exciton oscillator strength by virtue of the dielectric confinement effect . In spite of the expectation of a considerable shortening of the radiative lifetime, it was observed to be slightly longer under our conditions.