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We investigate the dominant phonon wavevectors q* and the associated dominant phonon-assisted electronic transitions implied by the 2D Raman mode of graphene by combining ab initio calculations with a full two-dimensional integration over the graphene Bril ...
An investigation is performed of the possibility of achieving simultaneous distributed strain and temperature sensing based on hybrid Raman–Brillouin scattering with the use of multi-wavelength optical sources such as common Fabry–Perot (FP) lasers. By emp ...
A distributed fiber-optic temperature sensor technique inherently allowing for system calibration, compensating time-dependent variations of the fiber losses as well as local external perturbations, is proposed using a loop-scheme together with Raman anti- ...
Effect of relaxation time on the performance of photonic crystal optical bistable switches based on Kerr nolinearity is discussed. This paper deals with optical pulses with the duration of about 50 ps. In such cases the steady state response of the optical ...
Spie-Int Soc Optical Engineering, Po Box 10, Bellingham, Wa 98227-0010 Usa2010
The polarization-related properties of stimulated Brillouin scattering (SBS) processes in long, randomly birefringent, standard optical fibers are examined. Evolution equations for the pump and signal waves, in the presence of both birefringence and SBS, a ...
A method to design planar multilayer meander-line polarizers is given. The proposed procedure is based on transmission line circuit theory and on full-wave unit cell analysis in frequency domain. The hybrid combination of those two techniques paves the way ...
Brillouin scattering is particularly efficient and attractive for the implementation of strain and temperature distributed sensing in optical fibres. Recently a trend has been observed that modern advanced applications require a substantial step towards be ...
A novel technique to realize true time reversal of an optical signal, using dynamic Brillouin gratings in high-birefringence fibers, is proposed. A data sequence of optical pulses with 2-ns duration was efficiently time-reversed. ...
We experimentally demonstrate that temporal differentiation of optical pulses can be realized in a slow & fast light system based on a resonance. The waveform of a 13 ns Gaussian pulse was experimentally first-order differentiated. ...
The energy transfer between the two interacting optical waves in a distributed sensor based on stimulated Brillouin scattering can lead to a non-uniform spectral distribution of the pumping power after a long propagation. This results in a spectrally disto ...