Spectral gaps and mode localization in Fibonacci chains of metal nanoparticles

Luca Dal Negro,Ning-Ning Feng

doi:10.1364/oe.15.014396

Abstract

In this paper we study the spectral, localization and dispersion properties of dipolar modes in quasi-periodically modulated nanoparticle chains based on the Fibonacci sequence. By developing a transfer matrix approach for the calculation of resonant frequencies, oscillation eigenvectors and integrated density of states (IDS) of spatially-modulated dipole chains, we demonstrate the presence of large spectral gaps and calculate the pseudo-dispersion diagram of Fibonacci plasmonic chains. The presence of plasmonic band-gaps and localized states in metal nanoparticle chains based on quasi-periodic order can have a large impact in the design and fabrication of novel nanophotonics devices.

Highlights

Quasi-periodic photonic structures are defined by simple mathematical rules which generate a non-periodic modulation of optical constants, encoding a fascinating complexity.→ → The Fibonacci sequence is the chief example of long-range order without periodicity, and can be generated according to the following inflation rule [1]: A AB, B A
In this paper we study the spectral, localization and dispersion characteristics of dipolar modes in quasi-periodically modulated nanoparticle chains based on the Fibonacci sequence
We calculate the integrated density of states (IDS) and pseudo-dispersion diagrams of Fibonacci chains, and we demonstrate the presence of large spectral gaps in quasi-periodic plasmonic systems

Summary

Introduction

Quasi-periodic photonic structures are defined by simple mathematical rules which generate a non-periodic modulation of optical constants, encoding a fascinating complexity.→ → The Fibonacci sequence is the chief example of long-range order without periodicity, and can be generated according to the following inflation rule [1]: A AB, B A. In this paper we study the spectral, localization and dispersion characteristics of dipolar modes in quasi-periodically modulated nanoparticle chains based on the Fibonacci sequence. Received 17 Jul 2007; revised 26 Sep 2007; accepted 1 Oct 2007; published 17 Oct 2007 29 October 2007 / Vol 15, No 22 / OPTICS EXPRESS 14397 calculate the resonant frequencies and dipole oscillation modes of a Fibonacci nanoparticles chain.

Results

Conclusion