We measured the decay rates of two degenerate surface plasmon modes in Au nanohole arrays with different hole sizes by angle-resolved reflectivity spectroscopy. For each hole size, at the spectral region where resonant coupling occurs, we observed a large modification in decay rates, leading to the formation of dark and bright modes. The change in decay rates is well explained by temporal coupled mode theory. The deduced coupling constant is found to increase with increasing hole diameter. This study provides us a simple and effective means to control the decay rates of dark and bright modes, which are useful in plasmonic applications.
© 2012 Optical Society of America
Optics at Surfaces
Original Manuscript: February 7, 2012
Revised Manuscript: April 16, 2012
Manuscript Accepted: May 10, 2012
Published: June 28, 2012
Hau-Yung Lo and Hock-Chun Ong, "Decay rates modification through coupling of degenerate surface plasmon modes," Opt. Lett. 37, 2736-2738 (2012)