| Title | The effects of excited state lifetime, optical intensity, and excited state quenchers on the photostability of zwitterionic chromophores |
| Publication Type | Journal Article |
| Year of Publication | 2011 |
| Authors | Williams, G.V.M., Kutuvantavida Y., Janssens S., Raymond S.G., Do M.T.T., Bhuiyan M.D.H., Quilty J.W., Denton N., and Kay A.J. |
| Journal | Journal of Applied Physics |
| Volume | 110 |
| Issue | 8 |
| Date Published | 2011 |
| ISSN | 00218979 (ISSN) |
| Keywords | Amorphous films, Amorphous polycarbonates, Beta carotene, Chromophores, energy transfer, Enhancement factor, Excited state lifetimes, Excited states, Excited-state energy, Fiber optic sensors, Nonlinear optic chromophores, Nonradiative decays, Optical correlation, Optical intensities, Oxygen, Oxygen content, Photo-stability, Photobleaching, PL lifetime, Singlet excited state |
| Abstract | Photoluminescence (PL) and photostability measurements have been made on thin films containing the 2nd order nonlinear optic chromophore, PYR-3, and amorphous polycarbonate (APC). We find that the PYR-3 singlet excited state PL lifetime systematically decreases with increasing PYR-3 concentration, which may be due to PYR-3 excited state energy transfer to non-radiative decay sites. There is no correlation between the PL lifetime and the photostability for low optical intensities, and we find that the photobleaching data cannot be modeled with a single photodegradation quantum efficiency. There is an increase in the photostability with increasing optical intensity, and this enhancement is larger for high PYR-3 concentrations. It can be explained by a reduction in the oxygen content by oxygen-mediated photodegradation for the 5 PYR-3/APC films. This also partly explains the enhancement in the 15 PYR-3/APC films, but there is an additional mechanism as well. The photostability can also be improved by adding beta-carotene, which leads to an enhancement factor of greater than 6. © 2011 American Institute of Physics. |
| URL | http://www.scopus.com/inward/record.url?eid=2-s2.0-80655139190&partnerID=40&md5=292353b741b5d192591473e9f234d25e |
| DOI | 10.1063/1.3632986 |
