Linear and nonlinear optical properties of pseudoisocyanine Jaggregates in distributed feedback microcavities

摘要

The linear and nonlinear optical properties of pseudoisocyaninen(PIC) J aggregates in 1-D distributed feedback (DFB) microcavities,nphotonic crystal slabs are investigated. The linear optical propertiesnare well described by the DFB cavity-polaritons in the slabs. Anpolariton mode splitting of 50 meV and a photonic band gap of 30 meV arenobserved in PIC J aggregates dispersed in a polyvinyl-alcohol matrix. Innthe pump and probe experiments, we resonantly excited the cavity modenobserved at the low energy side of the excitonic resonance, thenvirtual-exciton excitation condition. The response time is about 0.5 ps,nwhich is approximately equal to the pump-pulse duration. We find thenenhancement of the optical nonlinearity to be one-order of magnitude innthe microcavity. Excitation of the dielectric-band mode is effective innenhancing the nonlinearity with an ultrafast response