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Title: Anomalous Dispersion in Reflection and Emission of Dye Molecules Strongly Coupled to Surface Plasmon Polaritons
We have studied dispersion of surface plasmon polaritons (SPPs) in the Kretschmann geometry (prism/Ag/dye-doped polymer) in weak, intermediate, and ultra-strong exciton–plasmon coupling regimes. The dispersion curves obtained in the reflection experiment were in good agreement with the simple model predictions at small concentrations of dye (Rhodamine 590, Rh590) in the polymer (Poly(methyl methacrylate), PMMA). At the same time, highly unusual multi-segment “staircase-like” dispersion curves were observed at extra-large dye concentrations, also in agreement with the simple theoretical model predicting large, small, and negative group velocities featured by different polariton branches. In a separate experiment, we measured angular dependent emission of Rh590 dye and obtained the dispersion curves consisting of two branches, one nearly resembling the SPP dispersion found in reflection and the second one almost horizontal. The results of our study pave the road to unparalleled fundamental science and future applications of weak and strong light—matter interactions.  more » « less
Award ID(s):
2301350 2112595 1856515
PAR ID:
10522446
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
MDPI
Date Published:
Journal Name:
Nanomaterials
Volume:
14
Issue:
2
ISSN:
2079-4991
Page Range / eLocation ID:
148
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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