dc.contributor.advisor | Lee, Chi H. | en_US |
dc.contributor.advisor | Herman, Warren N. | en_US |
dc.contributor.author | Kim, Younggu | en_US |
dc.date.accessioned | 2007-02-01T20:22:40Z | |
dc.date.available | 2007-02-01T20:22:40Z | |
dc.date.issued | 2006-12-08 | en_US |
dc.identifier.uri | http://hdl.handle.net/1903/4164 | |
dc.description.abstract | The primary objective of this thesis is to explore the functionalities of new classes
of novel organic materials and investigate their technological feasibilities for becoming
novel photonic components.
First, we discuss the unique polarization properties of optical chiral waveguides.
Through a detailed experimental polarization analysis on planar waveguides, we
show that eigenmodes in planar chiral-core waveguides are indeed elliptically polarized
and demonstrate waveguides having modes with polarization eccentricity
of 0.25, which agrees very well with recent theory. This is, to the best of our
knowledge, the first experimental demonstration of the mode ellipticities of the
chiral-core optical waveguides. In addition, we also examine organic magneto-optic
materials. Verdet constants are measured using balanced homodyne detection, and
we demonstrate organic materials with Verdet constants of 10.4 and 4.2 rad/T · m
at 1300 nm and 1550 nm, respectively.
Second, we present low-loss waveguides and microring resonators fabricated
from perfluorocyclobutyl copolymer. Design, fabrication and characterization of
these devices are addressed. We demonstrate straight waveguides with propagation
losses of 0.3 dB/cm and 1.1 dB/cm for a buried channel and pedestal structures,
respectively, and a microring resonator with a maximum extinction ratio of 4.87 dB,
quality factor Q = 8554, and finesse F = 55. In addition, from a microring-loaded
Mach-Zehnder interferometer, we demonstrate a modulation response width of
30 ps and a maximum modulation depth of 3.8 dB from an optical pump with a
pulse duration of 100 fs and a pulse energy of 500 pJ when the signal wavelength
is initially tuned close to one of the ring resonances.
Finally, we investigate a highly efficient organic bulk heterojunction photodetector
fabricated from a blend of P3HT and C<sub>60</sub>. The effect of multilayer thin
film interference on the external quantum efficiency is discussed based on numerical
modeling. We experimentally demonstrate an external quantum efficiency
η<sub>EQE</sub>=87±2% under an applied bias voltage V = −10 V, leading to an internal
quantum efficiency η<sub>IQE</sub>≈97%. These results show that the charge collection
efficiency across the intervening energy barriers can indeed reach near 100% under
a strong electric field. | en_US |
dc.format.extent | 3439990 bytes | |
dc.format.mimetype | application/pdf | |
dc.language.iso | en_US | |
dc.title | Novel Organic Polymeric and Molecular Thin-Film Devices for Photonic Applications | en_US |
dc.type | Dissertation | en_US |
dc.contributor.publisher | Digital Repository at the University of Maryland | en_US |
dc.contributor.publisher | University of Maryland (College Park, Md.) | en_US |
dc.contributor.department | Electrical Engineering | |
dc.subject.pqcontrolled | Engineering, Electronics and Electrical | en_US |
dc.subject.pqcontrolled | Physics, Optics | en_US |
dc.subject.pquncontrolled | organic | en_US |
dc.subject.pquncontrolled | photonics | en_US |
dc.subject.pquncontrolled | integrated-optics | en_US |
dc.subject.pquncontrolled | optical communications | en_US |