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Y Dumeige

Publications and source records attributed to Y Dumeige.

3 recordsLinked to original sources
PubMed2003

Second-harmonic generation in one-dimensional photonic edge waveguides.

Diffraction losses in one-dimensional photonic crystal (PC) waveguides are the primary limitation on second-harmonic (SH) conversion efficiency. By using a finite difference time domain (FDTD) code taking into account second-order nonlinear polarization, we investigated these losses numerically, particularly at the SH wavelength. We propose an efficient SH conversion scheme in Al(x)Ga(1-x)As/air-etched waveguides. An analytical model is used to extrapolate the conversion efficiency to a number of periods for which time consumption makes the FDTD codes unsuitable.

Journal Article↗
PubMed2002

Phase-matched frequency doubling at photonic band edges: efficiency scaling as the fifth power of the length.

By exploiting the unique properties of periodic stratified media we demonstrate simultaneously phase matching and enhancement of the optical field under second order nonlinear interaction. This leads to a second harmonic efficiency growth faster than the fifth power of the structure length, far better than the usual quadratic behavior associated with second order nonlinear effects.

Journal Article↗
PubMed2001

Photonic band edge effects in finite structures and applications to chi 2 interactions.

Using the concept of an effective medium, we derive coupled mode equations for nonlinear quadratic interactions in photonic band gap structures of finite length. The resulting equations reveal the essential roles played by the density of modes and effective phase matching conditions necessary for the strong enhancement of the nonlinear response. Our predictions find confirmation in an experimental demonstration of significant enhancement of second harmonic generation near the photonic band edge. The measured conversion efficiency is in good agreement with the conversion efficiency predicted by the effective-medium model.

Journal Article↗