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Abstract We studied dispersion in Rhodamine laser dyes in the Kretschmann geometry and found (i) multi-branch “staircase” dispersion curves in singly doped and double doped PMMA polymer, (ii) emergence of the new dispersion “fork” branch, (iii) unparallel dispersion and coupling in the mixture of two different dyes, and (iv) effect of high dye concentration on strong coupling without metal.
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Concentration dependence of two-photon absorption in PMMA polymeric films doped with rhodamine laser dyes
We have studied poly(methyl methacrylate) (PMMA) films doped with rhodamine 6G and rhodamine B laser dyes as potential nonlinear material components for nanophotonics. For both dyes, the optimal concentrations, at which the emission excited via the two-photon-absorption (TPA) process is maximized, have been determined. Despite relatively large values of TPA cross sections obtained in this study, the characteristic pumping densities needed to observe pronounced nonlinear effects substantially exceed the laser damage threshold for Au or alternative plasmonic materials. This makes the studied laser dyes unsuitable for some of the intended nanophotonics applications.
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- PAR ID:
- 10194082
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Journal of the Optical Society of America B
- Volume:
- 37
- Issue:
- 10
- ISSN:
- 0740-3224; JOBPDE
- Format(s):
- Medium: X Size: Article No. 3108
- Size(s):
- Article No. 3108
- Sponsoring Org:
- National Science Foundation
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