Detuned Electrical Dipoles for Plasmonic Sensing

作者：Evlyukhin Andrey B; Bozhevolnyi Sergey I^*; Pors Anders; Nielsen Michael G; Radko Ilya P; Willatzen Morton; Albrektsen Ole

来源：Nano Letters, 2010, 10(11): 4571-4577.

DOI：10.1021/nl102572q

• Plasmonics
• localized surface plasmons
• plasmonic sensing

we demonstrate that a pair of electrical dipolar scatterers resonating at different frequencies, i.e., detuned electrical dipoles, can be advantageously employed for plasmonic sensing of the environment, both as an individual subwavelength-sized sensor and as a unit cell of a periodic array. It is shown that the usage of the ratio between the powers of light scattered into opposite directions (or into different diffraction orders), which peaks at the intermediate frequency, allows one to reach a sensitivity of approximate to 400 nm/RIU with record high levels of figure of merit exceeding 200. Qualitative considerations are supported with detailed simulations and proof-of-principle experiments using lithographically fabricated gold nanorods with resonances at similar to 800 nm.

• 出版日期2010-11