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dc.contributor.advisor Kono, Junichiro
dc.creatorSearles, Thomas A., Jr.
dc.date.accessioned 2013-03-08T00:38:47Z
dc.date.available 2013-03-08T00:38:47Z
dc.date.issued 2012
dc.identifier.urihttps://hdl.handle.net/1911/70438
dc.description.abstract Single-walled carbon nanotubes (SWNTs) are one of the leading candidate materials to realize novel nanoscale photonic devices. In order to assess their performance characteristics as optoelectronic materials, it is crucial to examine their optical properties in highly non-equilibrium situations such as high magnetic fields, low temperatures, and under high photoexcitation. Therefore, we present our latest result on the magnetic susceptibility anisotropy of metallic carbon nanotubes due to the Aharonov-Bohm effect. Here, we performed magnetic linear dichroism on a metallic-enriched HiPco SWNT sample utilizing a 35 T Hybrid Magnet to measure absorption with light polarization both perpendicular and parallel to the magnetic field. By relating these values with the nematic order parameter for alignment, we found that the metallic carbon nanotubes do not follow a strict diameter dependence across the 7 chiralities present in our sample. In addition to the studying the absorption properties exhibited at high magnetic field, we performed temperature-dependent (300 K to 11 K) photoluminescence (PL) on HiPco SWNTs embedded in an ι -carrageenan matrix utilizing intense fs pulses from a wavelength-tunable optical parametric amplifier. We found that for each temperature the PL intensity saturates as a function of pump fluence and the saturation intensity increases from 300 K to a moderate temperature around 100-150 K. Within the framework of diffusion-limited exciton-exciton annihilation (EEA), we successfully estimated the density of 1D excitons in SWNTs as a function of temperature and chirality. These results coupled with our results of magnetic brightening, or an increase in PL intensity as a function of magnetic flux through each SWNT due to the Aharonov-Bohm effect, yield great promise that in the presence of a high magnetic field the density of excitons can be further increased.
dc.format.extent 137 p.
dc.format.mimetype application/pdf
dc.language.iso eng
dc.subjectApplied sciences
Pure sciences
Carbon nanotubes
Single-walled carbon nanotubes
Photoexcitation
Condensed matter physics
Nanotechnology
dc.title Optical Spectroscopy of Single-Walled Carbon Nanotubes Under Extreme Conditions
dc.identifier.digital SearlesT
dc.type.genre Thesis
dc.type.material Text
thesis.degree.department Applied Physics
thesis.degree.discipline Natural Sciences
thesis.degree.grantor Rice University
thesis.degree.level Doctoral
thesis.degree.name Doctor of Philosophy
dc.identifier.citation Searles, Thomas A., Jr.. "Optical Spectroscopy of Single-Walled Carbon Nanotubes Under Extreme Conditions." (2012) Diss., Rice University. https://hdl.handle.net/1911/70438.


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