Study On Active Plasmonic Devices Integrated On LED Chip

Surface Plasmon Polariton (SPP) is a kind of the electromagnetic surface mode, arising from the electron oscillation while excitated by external light incidence. Owing to its particular properties of field confiment and enhancement, SPPs promise great application potential in wide range areas of optical signal process in micro/nano scale, new optical source, high sensitivity sensors and solar cells. Aiming to the electro-optical integration, this thesis investigated the coupling and propagation properties of SPPs, localized resonance and polarization control of plasmonic structure, designed and realized two types of active plasmonic devices based on the light emitting diode (LED) chip. The main content includes:Firstly, a metal grating was particularly designed on the surface of GaAs based LED chip, by which SPPs were directly coupled from the LED illumination with an electrical excitation. Thus an electrical pumped SPP source was realized. Compared to the conventional grating coupler with bidirectional launching of SPP, which results in at least half energy wasted, we developed this coupler to a well designed tiltled one that allows a unidirectional coupling (a ratio about10:1) and improved coupling efficiency (70%higher than conventional one). It revealed a propagation length about13um, allowing a space for futher manipulations of the SPPs.Secondly, we introduced an EOT structure with rectangular holes in metal film on the top of LED chip. The emission intensity and polarization properties were investigated with respect various structural parameters in detail, in which the influences of localized shape resonance and period modulated SPP are studied. More importantly, spatial distributed hole orientations were introduced according to the modulation of local polarization, which gave results to the polarization tuned binary encoding, single and double image display, animation movies. These results indicate possible application potentials in developing new kind of imaging and display devices.