Progress in nanophotonic devices driven by optical near-field

Abstract

In this paper, we review recent progress in nanophotonic devices using optical near-field interaction. ZnO nanocrystallites are potentially ideal components for realizing room-temperature operation of nanophotonic devices because of their high exciton-binding energy and great oscillator strength. To confirm this promising optical property of ZnO, we report the near-field time-resolved spectroscopy of ZnO nanorod double-quantum-well structures (DQWs). First, we observed nutation of the population between the resonantly coupled exciton states of DQWs, in which the coupling strength of the near-field interaction was found to be decreased exponentially as the separation increased. Furthermore, we successfully demonstrated the switching dynamics of a dipole-forbidden optical energy transfer among resonant exciton states. Our results provide criteria for designing nanophotonic devices.