Open AccessHollow-core PCF for guidance in the mid to far infra-red
Author(s) -
G. J. Pearce,
J.M. Pottage,
D. M. Bird,
Pamela Roberts,
J.C. Knight,
P. St. J. Russell
Publication year - 2005
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/opex.13.006937
Subject(s) - refractive index , optics , core (optical fiber) , materials science , photonic crystal fiber , bandwidth (computing) , optical fiber , optoelectronics , physics , telecommunications , computer science
A major limitation to attaining low-loss single-mode guidance in hollow core photonic crystal fibre (PCF) is surface guided modes that are trapped in the core surround. This is particularly severe when high index (n > 2) glasses are used. By modelling a structure that has the characteristic features of a realistic fibre we show that, by tuning the thickness of the core wall, the influence of these 'surface' modes can be minimised. For a refractive index of 2.4 we predict power-in-air fractions of over 95% over a fractional bandwidth of ~ 5%, peaking at over 98%. The designs are appropriate for mid- to far-IR PCFs for which suitable glasses (e.g., tellurites and chalcogenides) have high refractive indices.