Showing papers by "Philip St. J. Russell published in 2001"
TL;DR: These findings demonstrate that ultrafast femtosecond pulses are not needed for efficient supercontinuum generation in photonic crystal fibers.
Abstract: The generation of a spatially single-mode white-light supercontinuum has been observed in a photonic crystal fiber pumped with 60-ps pulses of subkilowatt peak power. The spectral broadening is identified as being due to the combined action of stimulated Raman scattering and parametric four-wave-mixing generation, with a negligible contribution from the self-phase modulation of the pump pulses. The experimental results are in good agreement with detailed numerical simulations. These findings demonstrate that ultrafast femtosecond pulses are not needed for efficient supercontinuum generation in photonic crystal fibers.
305 citations
TL;DR: Three new miniature devices are described: a fused fiber microcoupler with an interaction length of 200 mum, a long-period grating made from a periodic chain of microtapers, and a new type of prolate whispering-gallery mode microcavity.
Abstract: A focused carbon dioxide laser beam is used to microstructure fibers that have already been narrowed by conventional fiber tapering. We describe three new miniature devices made with this technique: a fused fiber microcoupler with an interaction length of 200 μm, a long-period grating made from a periodic chain of microtapers, and a new type of prolate whispering-gallery mode microcavity.
155 citations
TL;DR: Frequency-resolved optical gating experiments combined with analysis and modal simulations suggest that the mechanism for the simultaneous generation of two visible radiation components is third-harmonic conversion of the fundamental pulse and its split Raman self-shifted component.
Abstract: By coupling femtosecond pulses at lambda - 1.55mum in a short length (Z - 95 cm) of photonic crystal fiber, we observe the simultaneous generation of two visible radiation components. Frequency-resolved optical gating experiments combined with analysis and modal simulations suggest that the mechanism for their generation is third-harmonic conversion of the fundamental pulse and its split Raman self-shifted component.
109 citations
Journal Article•
60 citations
26 Mar 2001
TL;DR: In this article, a supercontinuum generation in a regime where the self-phase modulation of the pump wave gives a negligible contribution to the spectral broadening reveals the importance of parametric and Raman effects in photonic crystal fibers.
Abstract: Supercontinuum generation in a regime where the self-phase-modulation of the pump wave gives a negligible contribution to the spectral broadening reveals the importance of parametric and Raman effects in photonic crystal fibers.
14 citations
11 May 2001
TL;DR: In this paper, an evanescent field coupler was demonstrated by selective heat-treating a region of a previously uncoupled twin core optical fiber with two or more cores.
Abstract: Summary form only given. Multicore fibers are optical fibers with two or more cores. The cores can be coupled or uncoupled depending on the properties of the fiber. Photonic crystal fiber (PCF) is an undoped all silica fiber with an array of air holes that run along its length. This novel type of optical fiber has some remarkable waveguiding properties that can be characterized by the size of the air holes and the distance between them. PCF is fabricated using a proven stack and draw technique, due to this unique fabrication process the inclusion of multiple cores, anywhere within the two-dimensional hexagonal lattice is significantly simpler than the fabrication of conventional step index fibers. In this paper we demonstrate an evanescent field coupler by selective heat-treating a region of a previously uncoupled twin core PCF.
14 citations
Patent•
03 May 2001
TL;DR: In this paper, a nonlinear optical device consisting of a source of input light having a first spectrum and an optical fibre 10 arranged so that in use the light propagates through the fibre 10, the optical fiber 10 comprises a tapered region including a waist 30, the waist 30 having a diameter smaller than 10 microns for a length of more than 20 mm.
Abstract: A nonlinear optical device, comprises a source of input light having a first spectrum and an optical fibre 10 arranged so that in use the light propagates through the fibre 10, the optical fibre 10 comprises a tapered region including a waist 30, the waist 30 having a diameter smaller than 10 microns for a length of more than 20 mm, wherein the propagating light is converted by nonlinear optical processes into output light having a spectrum different from the first spectrum
8 citations
30 Jul 2001
TL;DR: The photonic crystal fiber (PCF) as mentioned in this paper is a new class of optical fiber that incorporates air holes that run along the length of the fibers cladding, and is made from a stack of close-packed silica tubes and rods that is drawn into fiber using a conventional fiber drawing tower.
Abstract: In 1996 we reported the first example of a photonic crystal fibre (PCF), an entirely new class of optical fiber. Also known as holey or microstructure fibers, they incorporate air holes that run along the length of the fibers cladding. The fiber is made from a stack of close-packed silica tubes and rods that is drawn into fiber using a conventional fiber drawing tower. We have demonstrated a wide variety of PCF designs and developed the conceptual tools needed to understand their properties and guide their design. These fibers can have highly unusual properties, and look set to rewrite the fibre-optics rulebook and revolutionize the future of optical telecommunication.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
6 citations
26 Mar 2001
TL;DR: In photonic crystal fibres, light is trapped within a central solid or hollow core by an encircling array of microscopic air holes as discussed by the authors, and many nonlinear applications are emerging, including efficient supercontinuum generation, gas-Raman amplifiers and cold atom guides.
Abstract: In photonic crystal fibres, light is trapped within a central solid or hollow core by an encircling array of microscopic air holes. Many nonlinear applications are emerging, including efficient supercontinuum generation, gas-Raman amplifiers and cold atom guides.
2 citations
08 May 2001
TL;DR: The photonic crystal fiber (PCF) as mentioned in this paper is a single-material all-silica structure with an array of microscopic air holes running along the entire length of the fiber, where light can be trapped by a modified form of total internal reflection (at a filled-in hole) or by a photonic bandgap (e.g., at an enlarged hole).
Abstract: Photonic crystal fiber (PCF) is a single-material all-silica structure. Initially proposed by the author in 1991, the first working example was reported at the Optical Fiber Communications Conference in 1996. In place of the conventional core and cladding, an array of microscopic air holes runs along the entire length of the fiber. Depending on the design, light can be trapped by two distinct mechanisms: a modified form of total internal reflection (at a filled-in hole) or by a photonic bandgap (e.g., at an enlarged hole). These unconventional fibers have led to a series of breakthroughs that is radically enhancing the performance of optical fibers. The disruptive implications of the new technology are just beginning to be worked out.
1 citations
06 May 2001
TL;DR: In this article, an acoustic defect mode trapped at the solid core in a square-lattice PCF preform was demonstrated, where the core acts as a defect of the phononic crystal and so elastic defect modes can be confined in this region.
Abstract: Summary form only given. Photonic crystal fibers (PCFs) were first demonstrated in 1996. They are all-silica fibers in which the cladding consists of a two-dimensional array of microscopic air holes running along their length. The central hole of the structure is missing, leaving a solid silica core to guide the light. The periodic nature of the cladding makes also possible the existence of acoustic band gaps. Moreover, the core can also act as a defect of the phononic crystal and so elastic defect modes can be confined in this region. Here we present the first experimental demonstration of an acoustic defect mode trapped at the solid core in a square-lattice PCF preform.
26 Mar 2001
TL;DR: By coupling femtosecond pulses at λ = 1.55 microns in a one meter segment of photonic crystal fiber, this article observed simultaneous generation of third harmonic frequencies from both the fundamental and its self-shifted Raman component, whereas no second harmonic signal is detected.
Abstract: By coupling femtosecond pulses at λ=1.55 microns in a one meter segment of photonic crystal fiber we observe simultaneous generation of third harmonic frequencies from both the fundamental and its self-shifted Raman component, whereas no second harmonic signal is detected.
09 Jun 2001
TL;DR: The photonic crystal fiber (PCF) as mentioned in this paper is a single-material all-silica structure with an array of microscopic air holes running along the entire length of the fiber, where light can be trapped by a modified form of total internal reflection (at a filled-in hole) or by a photonic bandgap (e.g., at an enlarged hole).
Abstract: Photonic crystal fiber (PCF) is a single-material all-silica structure. Initially proposed by the author in 1991, the first working example was reported at the Optical Fiber Communications Conference in 1996. In place of the conventional core and cladding, an array of microscopic air holes runs along the entire length of the fiber. Depending on the design, light can be trapped by two distinct mechanisms: a modified form of total internal reflection (at a filled-in hole) or by a photonic bandgap (e.g., at an enlarged hole). These unconventional fibers have led to a series of breakthroughs that is radically enhancing the performance of optical fibers. The disruptive implications of the new technology are just beginning to be worked out.