Showing papers by "Pierre Mathieu published in 2014"
TL;DR: The efficiency and spectral shape of the SC produced by ultrashort pulses in large-core As2S3 fiber are mainly determined by its dispersion, the S-H contaminant absorption, and the mid-infrared nonlinear absorption.
Abstract: We report on infrared supercontinuum (SC) generation through laser filamentation and subsequent nonlinear propagation in a step-index As2S3 fiber. The 100 μm core and high-purity As2S3 fiber used exhibit zero-dispersion wavelength around 4.5 μm, a mid-infrared background loss of 0.2 dB/m, and a maximum loss of only 0.55 dB/m at the S-H absorption peak around 4.05 μm. When pumping with ultrashort laser pulses slightly above the S-H absorption band, broadband infrared supercontinua were generated with a 20 dB spectral flatness spanning from 1.5 up to 7 μm. The efficiency and spectral shape of the SC produced by ultrashort pulses in large-core As2S3 fiber are mainly determined by its dispersion, the S-H contaminant absorption, and the mid-infrared nonlinear absorption.
60 citations
TL;DR: The explicit formula for the superconformal singular vectors in the Neveu-Schwarz sector has been obtained recently, via its symmetric polynomial representation, as a sum of superpolynomials as mentioned in this paper.
Abstract: The explicit formula for the superconformal singular vectors in the Neveu–Schwarz sector has been obtained recently, via its symmetric polynomial representation, as a sum of Jack superpolynomials. Here we present the analogous, but slightly more complicated, closed-form expression for the Ramond singular vectors.
9 citations
TL;DR: In this paper, the degenerate Whittaker vector of superconformal algebra can be represented in terms of superpolynomials and a closed-form expression for the norm of this vector is given.
Abstract: The degenerate Whittaker vector of the superconformal algebra can be represented in terms of Jack superpolynomials. However, in this representation the norm of the Whittaker vector involves a scalar product with respect to which the Jack superpolynomials are not orthogonal. In this note, we point out that this defect can be cured at c = 3/2 by means of a trick specific to the supersymmetric case. At c = 3/2, we thus end up with a closed-form expression for the norm of the degenerate super-Whittaker vector. Granting the super-version of the AGT conjecture, this closed-form expression should be equal to the -symmetric SU(2) pure-gauge instanton partition function—the corresponding equality taking the form of a rather nontrivial combinatorial identity.
1 citations