Excitation of a nanowire “molecule” in gold-filled photonic crystal fibre

31.10.2012, 14:59

Newsletter 5

High pressure melt-filling of selected hollow channels with gold is now a routine procedure in photonic crystal fibres. The technique provides an elegant means of studying the optical properties of surface plasmon-polariton (SPP) modes guided on metallic nanowires embedded in the PCF cladding. In previous experiments we have shown that when light couples from the glass core to one of the SPP modes on a single gold nanowire, a dip appears in the transmission spectrum at a certain resonant wavelength lambda0. In recent experiments we have repeated this study with two adjacent gold nanowires. This nanowire pair behaves like a "diatomic molecule", supporting hybridized bonding and anti-bonding super-modes that phase match to the core mode at wavelengths lying on either side of lambda0, separated by 100 nm. The dispersion and attenuation of these hybrid modes is quite different from the SPP mode of a single gold nanowire. The results provide insight into multiwire plasmonic devices with potential applications as polarizers or filters in near-field optics, nonlinear plasmonics, optical sensing and telecommunications.

 

Contact: philip.russell(at)mpl.mpg(dot)de
Group: Russell Division
Reference: H. W. Lee et al., Opt. Lett. 37, 2946–2948 (2012); highlighted in Nat. Phot. 6, 501 (2012).