Band-gap engineering in two-dimensional periodic photonic crystals

Abstract

A theoretical investigation is made of the dispersion characteristics of plasmons in a twodimensional periodic system of semiconductor (dielectric) cylinders embedded in a dielectric (semiconductor) background. We consider both square and hexagonal arrangements and calculate extensive band structures for plasmons using a plane-wave method within the framework of a local theory. It is found that such a system of semiconductor-dielectric composite can give rise to huge full band gaps (with a gap to midgap ratio ≈ 2) within which plasmon propagation is forbidden. The most interesting aspect of this investigation is the huge lowest gap occurring below a threshold frequency and extending up to zero. The maximum magnitude of this gap is defined by the plasmon frequency of the inclusions or the background as the case may be. In general we find that greater the dielectric (and plasmon frequency) mismatch, the larger this lowest band-gap. Whether or not some higher energy gaps appear, the lowest gap is always seen to exist over the whole range of filling fraction in both geometries. Just like photonic and phononic band-gap crystals, semiconducting band-gap crystals should have important consequences for designing useful semiconductor devices in solid state plasmas.

Classical vibrational modes in phononic lattices: theory and experiment

“…The most important aspect of these results is the cutoff frequency W c below which no propagation at all is allowed. In this sense, the situation here is comparable to the semiconductor-dielectric photonic crystals investigated in [159,160]. Note that all three gaps start opening up at a vanishingly small but finite value of b L and that the lowest gap remains the widest one over the whole range of the stub width.…”

Wave propagation and instabilities in monolithic and periodically structured elastomeric materials undergoing large deformations

“…Many solid-solid, solid-fluid, and solid-air structures have been pursued through experiments and/or simulation. [2][3][4][5][6][7][8][9][10][11][12][13][14] Moreover studies have focused on the sound-light interplay in periodic systems. [15][16][17] Recently solids with periodicity at the sub-micron scale have attracted increasing attention.…”

Elastic Wave Localization in Layered Phononic Crystals With Fractal Superlattices

“…In 1993, Kushwaha [7] introduced the concept of "PNCs", which represent a kind of artificial periodic elastic/acoustic structures that exhibit the so-called "phononic band gaps." Since then, considerable attention has been focused on PNCs and many results have been obtained for both ordered [8][9][10], disordered [11], and defected [12] systems.…”