Showing papers by "Philip St. J. Russell published in 2006"
TL;DR: This work shows how few-GHz acoustic phonons acquire many of the same characteristics as optical phonons when they are tightly trapped, transversely and close to modal cut-off, inside the wavelength-scale core of an air-glass photonic crystal fiber (PCF).
Abstract: Raman and Brillouin scattering are normally quite distinct processes that take place when light is resonantly scattered by, respectively, optical and acoustic phonons. We show how few-GHz acoustic phonons acquire many of the same characteristics as optical phonons when they are tightly trapped, transversely and close to modal cut-off, inside the wavelength-scale core of an air-glass photonic crystal fiber (PCF). The result is an optical scattering effect that closely resembles Raman scattering, though at much lower frequencies. We use photoacoustic techniques to probe the effect experimentally and finite element modelling to explain the results. We also show by numerical modelling that the cladding structure supports two phononic band gaps that contribute to the confinement of sound in the core.
107 citations
TL;DR: Based on the measurements, this work proposes two schemes for simultaneous strain and temperature measurement using a single unmodified PCF element, without a requirement for any compensating components, and project the measurement accuracies of these schemes.
Abstract: We report on a low-coherence interferometric scheme for the measurement of the strain and temperature dependences of group delay and dispersion in short, index-guiding, 'endlessly-single-mode' photonic crystal fibre elements in the 840 nm and 1550 nm regions. Based on the measurements, we propose two schemes for simultaneous strain and temperature measurement using a single unmodified PCF element, without a requirement for any compensating components, and we project the measurement accuracies of these schemes.
10 citations
TL;DR: In this paper, progress in nonlinear optics is allowing expansion of development in ultrafast ultrafast broadband and ultraviolet sources, and the authors propose a method to exploit this progress for ultra fast broadband and UV sources.
Abstract: Progress in nonlinear optics is allowing expansion of development in ultrafast
broadband and ultraviolet sources.
5 citations
21 May 2006
TL;DR: In this article, strong in-plane confinement of acoustic phonons in air-glass PCFs with sub-wavelength-scale cores is shown to result in an acoustic mode cut-off frequency, which acts like a Raman resonance.
Abstract: Strong in-plane confinement of acoustic phonons in air-glass PCFs with sub-wavelength-scale cores is shown to result in an acoustic mode cut-off frequency, which acts like a Raman resonance. Spontaneous and photoacoustic measurements illustrate the effect.
1 citations
21 May 2006
TL;DR: In this article, a dasiashark-finpsila-shaped feature in the power-dependent spectrum was observed in an adiabatically tapered photonic crystal fiber.
Abstract: We report new nonlinear features observed in an adiabatically tapered photonic crystal fiber. When using femtosecond pulses, the soliton self-frequency shift and generation of nonsolitonic radiation result in a dasiashark-finpsila-shaped feature in the power-dependent spectrum.
01 Sep 2006
TL;DR: In this article, the photochemical fabrication of a long-period grating in photonic crystal fiber is described. But the characteristic fluence value for inscription is an order of magnitude less than that for standard telecom fiber.
Abstract: We report on the photochemical fabrication of a long-period grating in photonic crystal fiber. The characteristic fluence value for inscription is an order of magnitude less than that for standard telecom fiber.