Nanophotonics for tailoring light-matter interaction/

In this thesis, we will theoretically explore three nanophotonics phenomena which enable strong light-matter interaction. The first phenomenon is plasmonic resonance, where the surface plasmon mode at metal and dielectric boundaries significantly enhances the optical response of nanoparticles. We propose an optimization-based theoretical approach to tailor the optical response of silver/silica multilayer nanospheres over the visible spectrum. We show that the structure that provides the largest cross-section per volume/mass, averaged over a wide frequency range, is the silver coated silica sphere. We also show how properly chosen mixture of several species of different nanospheres can have an even larger minimal cross-section per volume/mass over the entire visible spectrum. The second phenomenon is photonic chiral edge state, where the breaking of time-reversal symmetry forces light to travel in only one direction. Based on the directional coupling between one-way waveguide and conventional two-waveguide, we propose a new type of optical circulators, which has the potential for simultaneous broadband operation and small device footprint. The third phenomenon is Stimulated Brillouin Scattering (SBS), where photon and phonon are coupled through optical forces such as electrostriction force and radiation pressure. We develop a general method of calculating SBS gain via the overlap integral between optical and elastic modes. Applying this method to a rectangular waveguide, we demonstrate that the distribution of optical force and elastic modal profile jointly determine the magnitude and scaling of SBS gains. Applying this method to a periodic waveguide, we demonstrate that SBS gain can be further enhanced in the slow light regime. Based on this framework, we theoretically characterize a novel class of hybrid photon-phonon waveguides. Our analysis reveals that photon-phonon coupling via SBS can be directed and tailored over an exceptionally wide frequency range, enabling a host of chip-scale filtering, delay, and signal processing schemes.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Physics.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2013

Author dc:creator

• Qiu, Wenjun

Advisor dc:contributor.advisor

• Marin Soljačić.

• Physics.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/79541

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/79541