Application of an ARROW model for designing tunable photonic devices

Abstract

Microstructured optical fibers with the low refractive index core surrounded by high refractive index cylindrical inclusions reveal several intriguing properties. Firstly, there is a guiding regime in which the fibers' confinement loss is strongly dependent of wavelength. In this regime, the positions of loss maxima are largely determined by the individual properties of high index inclusions rather than their position and number. Secondly, the spectra of these fibers can be tuned by changing the refractive index of the inclusions. In this paper we review transmission properties of these fibers and discuss their potential applications for designing tunable photonic devices.

Bandgaps and antiresonances in integrated-ARROWs and Bragg fibers; a simple model

“…As it was initially conceived, the model used to describe ARROWs typically assumed that one of the cladding layer refractive indices was much greater than the core and remaining cladding index [15]. As such, many ARROW designs have a core index equal to the lowest of the cladding indices [15][16][17][18][19][20][21]; we will call these level-core waveguides. Indeed, this line of thought saw the ARROW model successfully applied to (non-layered cladding) photonic crystal fibers (PCFs) [20,21] and has spawned much interest in what have been termed 'ARROWfibers': PCFs of a low-index substrate with a cladding of high-index rods (typically on, but not restricted to, a hexagonal lattice).…”

“…As such, many ARROW designs have a core index equal to the lowest of the cladding indices [15][16][17][18][19][20][21]; we will call these level-core waveguides. Indeed, this line of thought saw the ARROW model successfully applied to (non-layered cladding) photonic crystal fibers (PCFs) [20,21] and has spawned much interest in what have been termed 'ARROWfibers': PCFs of a low-index substrate with a cladding of high-index rods (typically on, but not restricted to, a hexagonal lattice). It is implicitly assumed that such fibers have a core refractive index equal to the surrounding low-index substrate, just like the early (level-core) ARROWs; rightly so, since it is structurally the only possibility for a 2-D lattice based cladding as opposed to a layered one.…”

“…Indeed, it is the Archambault-ARROW model that is considered for most current work on integrated hollowcore ARROWs [10,11]. We believe this disparity between the use of the general Archambault-ARROW model and its restricted, Duguay-ARROW-based [15], form as applied to PCFs (the 'ARROW-fibers') [18][19][20][21] is responsible for the apparent bifurcation of the use of the ARROW principle in the integrated-waveguide and fiber fields. This is most clearly demonstrated (to the best of the Authors' knowledge) by the absence of antiresonance analyses for hollow-core Bragg fibers and the absence of a Bloch analysis for hollow-core integrated-ARROWs; the two waveguide structures being fundamentally similar (depressed core, binary layered cladding), as discussed.…”

“…We coin this new model the Stratified Planar Anti-Resonant Reflecting Optical Waveguide (SPARROW) model to distinguish it from both the original Archambault-ARROW model itself [9] and, in particular, the more restrictive level-core ARROW and (non-stratified) PCF applications based on the Duguay-ARROW model [15,[19][20][21]. Indeed, as will be shown later (Section 4.3), the Duguay-ARROW model is a special case of the SPARROW model (found by enforcing a level-core index profile).…”

Analysis on Transition between Index- and Bandgap-guided Modes in Photonic Crystal Fiber

“…All-solid photonic bandgap fiber (ASPBGF) is a type of bandgap-guiding PCF. This has been made of high refractive index material (HRIM) inserts embedded in a PCF preform or filled into PCF afterwards [8][9][10][11][12][13][14]. Unusual dispersive properties have been also observed in the fiber, so the ASPBGFs were often applied to femtosecond laser and amplifier developments [15][16][17].…”