(2) The refractive index sensitivity of single-mode LSPR in nanoparticles is independent of the resonance mode of choice and the particle geometry provided that the sensing wavelength is fixed. (3) The improved FOM observed for plasmonic quadrupole resonances in gold nanoparticles in the present work as well as in previous VX-680 order studies is due mainly to the reduction of resonance
linewidth. Our results suggest that plasmonic quadrupole modes in gold nanorods are possibly the most promising choice to achieve the best sensing performance and that it is of particular importance to explore multipolar resonances for further sensing studies. Acknowledgements This work was supported by the Hong Kong Polytechnic University (Projects 1-ZVAL, 1-ZVAW, and PD0332991 A-PL53), and the National High Technology Research and Development Program of China (863 Program) under Grant 2013AA031903. The authors
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