Tailoring modal properties of inhibited-coupling guiding fibers by cladding modification

Abstract

Understanding cladding properties is crucial for designing microstructured optical fibers. This is particularly acute for Inhibited-Coupling guiding fibers because of the reliance of their core guidance on the core and cladding mode-field overlap integral. Consequently, careful planning of the fiber cladding parameters allows obtaining fibers with optimized characteristics such as low loss and broad transmission bandwidth. In this manuscript, we report on how one can tailor the modal properties of hollow-core photonic crystal fibers by adequately modifying the fiber cladding. We show that the alteration of the position of the tubular fibers cladding tubes can alter the loss hierarchy of the modes in these fibers, and exhibit salient polarization propriety. In this context, we present two fibers with different cladding structures which favor propagation of higher order core modes – namely LP11 and LP21 modes. Additionally, we provide discussions on mode transformations in these fibers and show that one can obtain uncommon intensity and polarization profiles at the fiber output. This allows the fiber to act as a mode intensity and polarization shaper. We envisage this novel concept can be useful for a variety of applications such as hollow core fiber based atom optics, atom-surface physics, sensing and nonlinear optics.

Mode-phase-difference photothermal spectroscopy for gas detection with an anti-resonant hollow-core optical fiber

“…5, the probe wavelength is simply tuned to a quadrature point of the interference fringe. Stable operation over a much longer term may be achieved by locking the probe laser wavelength to a fringe quadrature via servocontrol, and by using polarization maintaining SMFs for light transmission and a dual-mode sensing HCF capable of maintaining polarization as well as lobe-orientation 27 .…”

Large array of Schrödinger cat states facilitated by an optical waveguide

“…Other than the fundamental importance, the plethora of photonic structures of fibres 38 provides fruitful ways for manipulating atoms. For example, the higher-order modes can be tailored to create multiple lattice sites and different polarisations in the transverse plane, creating a three-dimensional atom array in a cylindrically symmetric photonic structure 39 . Strong atom–light interactions can be achieved by trapping atoms in the cladding modes, which can be patterned by engineering the geometry and thickness of the cladding structure 40 .…”

Hollow-Core Fibers with Specific Modal Operation and Low Loss in the Short-Wavelength Range

“…In this section, we describe two examples where a judicious choice of the fiber cladding allows obtaining fibers with unique modal operation. The first example consists of SR-TL HC-PCFs with modified azimuthal cladding tubes distribution able to favor the propagation of specific higher-order modes (HOMs) [16]. The second example concerns a new HC-PCF design, the hybrid kagome-tubular lattice (HKT) HC-PCF, which allows obtaining effective single-mode operation and low attenuation levels [17].…”

“…This alteration entails enlargement of the spacing between selected tubes and implies higher leakage of the fundamental mode, whereas weakly affecting the CL of the HOMs. [16] Figure 1a exposes two fiber designs (FD) that illustrate the concept of CL hierarchy modification: an SR-TL HC-PCF with homogeneous spacing between the lattice tubes (FD#1) and an HC-PCF with larger spacing between the lattice tubes at 180 o (FD#2). Likewise, Figure 1a presents the simulated CL of representative modes.…”