High-fidelity, low-latency polarization quantum state transmissions over a hollow-core conjoined-tube fiber at around 800  nm

Abstract

The performances of optical fibre-based quantum information systems are limited by the intrinsic properties of silica glass materials, e.g. high latency, Rayleigh-scattering loss wavelength scaling law, and cross-coupling induced modal impurity. Hollow-core optical fibre (HCF) promises to unify air-borne light propagation and non-line-of-sight transmission, thus holding great potentials for versatile photonics-based quantum information applications. The early version of HCF based on photonic-bandgap guidance has not proven itself as a reliable quantum channel because of the poor modal purity in both spatial and polarization domains, as well as significant difficulty in fabrication when the wavelength shifts to the visible region. In this work, based on the polarization degree of freedom, we first, to the best of our knowledge, demonstrate high-fidelity (~0.98) single-photon transmission and distribution of entangled photons over a conjoined-tube hollow-core fibre (CTF) by using commercial silicon single-photon avalanche photodiodes. Our CTF realized the combined merits of low loss, high spatial mode purity, low polarization degradation, and low chromatic dispersion. We also demonstrate single-photon low latency (~99.96% speed of light in vacuum) transmission, thus paving the way for extensive uses of HCF links in versatile polarization-based quantum information processing.

Hollow-core fibers with reduced surface roughness and ultralow loss in the short-wavelength range

“…In the above-mentioned analyses, we used = 1700 nm. Also, we mention that different C 0 values in the MBL formula have been considered (from 0 to 2.86 33 ), and the ratio of the rms roughness suppression was found to be in the range of 2.3–2.7.…”

“…In turn, is the power lost by the core fundamental mode and is the power transferred from the fundamental mode to the LP 11 -like modes 32 . Herein, we used 33 . It is worth mentioning, however, that although we present the MBL contributions corresponding to our fibers so as to situate our results among the other studies available in the literature, we consider the description of the MBL in HCPCFs as a model still in construction which calls out for further studies by the HCPCF community.…”

Analytical Formulas for Micro-Bending and Surface Scattering Loss Estimation in Tube Lattice Fibers

“…( 11), together with Eqs. (8), and ( 13), and the mathematical expression of Φ(∆β), permits to analytically estimate the M BL.…”

“…More precisely, Hollow-Core Inhibited Coupling Fibers (HC-ICFs) exhibit much better performance than Photonic Band-Gap Fibers in terms of lower loss, wider bandwidth, lower dielectric interaction, better and more flexible management of the effectively single-mode condition. Thanks to that, several applications in the fields of sensing [2], [3], optical communications [4], fiber lasers [5], high power delivery [6], [7], nonlinear optics [1], and quantum applications [8] have been demonstrated in the last few years. One of the main issues of HC-ICFs is the propagation loss (PL), which has as its lower theoretical limit the confinement loss (CL) related to the intrinsically leaky nature of their guided modes.…”

Azimuthal Fourier Decomposition for Loss Analysis of Hollow-Core Tube Lattice Fibers Part I: Ideal Fibers

“…M ODERN optical systems require light guidance media that combine highly sought features such as very low loss, high power-handling capabilities, and strong interaction with gases and liquids. Hollow-core photonic-crystal fibers (HC-PCFs) are highly investigated in this regard as they offer the ability to satisfy all these features at the same time, owing to their ability to guide light in a hollow core where it has minimal interaction with the dielectric cladding, making them attractive in applications as diverse as gas lasers [1], [2], lightgas interaction [3], [4], terahertz systems [5], gas and biosensing [6]- [8], classical [9] and quantum communications [10].…”