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Dear Colleagues,<br><br>
The G.R. Harrison Spectroscopy Laboratory and the Department of
Electrical Engineering and Computer Science would like to invite you to
the next seminar in our series on Modern Optics and
Spectroscopy.<br><br>
<br>
Date &
Time:<x-tab> </x-tab><x-tab> </x-tab>Tuesday,
November 30, 12 noon - 1 PM<br>
Location:<x-tab> </x-tab><x-tab> </x-tab>Grier
Room (34-401)<br>
Speaker:<x-tab> </x-tab><x-tab> </x-tab><b>Shin
Grace Chou,</b> Massachusetts Institute of Technology<br>
Title:
<x-tab> </x-tab><x-tab> </x-tab><i>The
novel photophysics in DNA-wrapped carbon nanotubes<br><br>
</i>Refreshments will be served following the talk.<br><br>
Abstract:<br>
<b>Shin Grace Chou,</b> Massachusetts Institute of Technology<br>
<i>The novel photophysics in DNA-wrapped carbon nanotubes<br>
</i>We have carried out a detailed resonance Raman and photoluminescence
(PL) spectroscopic study on a (6,5)-enriched single wall carbon nanotube
sample that has been dispersed and isolated using single stranded
DNA. Multiple intense PL peaks are observed at excitation energies
that do not correspond to singularities in electronic density of states,
where resonantly enhanced optical transitions occur. The observed
PL peaks are assigned to different mechanisms of excitonic excitation and
relaxation, including one-phonon, two-phonon, and hot luminescence
processes, as well as radiative and non-radiative energy transferring
mechanisms between neighboring nanotubes. The study shows that the
excitonic relaxation processes observed in photoluminescence spectra can
be used as a means of probing the different physical interactions between
photons, carriers, and phonons that are not separately identified in bulk
semiconductor materials.<br>
<x-sigsep><p></x-sigsep>
Vinnie Russo * vrusso@mit.edu * Office Manager<br>
MIT; G.R. Harrison Spectroscopy Laboratory<br>
77 Mass. Ave., 6-014 * Cambridge, MA 02139<br>
(v) 617-253-9774 * (f) 617-253-4513 <br>
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<br>
<div>Vinnie Russo * vrusso@mit.edu * Office Manager</div>
<div>MIT; G.R. Harrison Spectroscopy Laboratory</div>
<div>77 Mass. Ave., 6-014 * Cambridge, MA 02139</div>
(v) 617-253-9774 * (f) 617-253-4513
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