Coupling fluorophores molecules to nanophotonic structures

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Abstract/Contents

Abstract
Fluorescence imaging and spectroscopy is an important tool in many areas of research. Biology has particularly benefitted from fluorescence techniques, since a single molecule's position, local environment, and even activity can be studied in real time by tagging it with a fluorescent label. It is, therefore, important to be able to understand and manipulate fluorescence. One way to control fluorescence is to shape the local electromagnetic fields that excite the fluorescent molecule. This thesis studies the interaction between fluorescent molecules and two nanophotonic structures that highly modify local electromagnetic fields: the bowtie nanoantenna and the photonic crystal cavity. The study of plasmons, or coherent excitations of free electrons in a metal, has led to the fabrication of antennas at optical frequencies. In particular, gold bowtie nanoantennas have been shown to concentrate light from the diffraction limit at 800 nm (~300 nm) down to ~20 nm, while also enhancing the local electric field intensity by a factor of 1,000. This huge change in the local field greatly alters the absorption and fluorescence emission of nearby molecules. This thesis will show that the fluorescence from an initially-poor single-molecule emitter can be enhanced by a factor of 1,300, allowing for the measurement of one highly enhanced molecule over a background of 1,000 unenhanced molecules. By extending this experiment to molecules in solution, dynamics of single molecules in concentrated solutions can also be measured. While bowtie nanoantennas act to concentrate light, light does not remain in the structure for long. The photonic crystal cavity can be used to trap and store light, which has interesting implications for molecular emitters located nearby. This thesis will show that molecules can be lithographically positioned onto a photonic crystal cavity and that the molecule's fluorescence emission is coupled to the cavity modes.

Description

Type of resource text
Form electronic; electronic resource; remote
Extent 1 online resource.
Publication date 2010
Issuance monographic
Language English

Creators/Contributors

Associated with Kinkhabwala, Anika Amir
Associated with Stanford University, Department of Applied Physics
Primary advisor Moerner, W. E. (William Esco), 1953-
Thesis advisor Moerner, W. E. (William Esco), 1953-
Thesis advisor Brongersma, Mark L
Thesis advisor Kino, Gordon S
Advisor Brongersma, Mark L
Advisor Kino, Gordon S

Subjects

Genre Theses

Bibliographic information

Statement of responsibility Anika Amir Kinkhabwala.
Note Submitted to the Department of Applied Physics.
Thesis Ph.D. Stanford University 2010
Location electronic resource

Access conditions

Copyright
© 2010 by Anika Amir Kinkhabwala
License
This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).

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