Linear and nonlinear optical properties of pseudoisocyanine J aggregates in distributed feedback microcavities: enhancement of the optical nonlinearity

Results of coherent transients of pseudoisocyanine J aggregates in distributed feedback microcavities are reported. Under resonant excitation of the cavity-mode observed at the low energy side of the excitonic resonance, the response time is less than 1 ps, approximately equal to the pump pulse duration. We find an enhancement of the optical nonlinearity by one-order of magnitude in the microcavity. The excitation of the cavity-mode is effective in enhancing the nonlinearity with ultrafast response.