arXiv subjects

J. C. A. Tyrrell

Publications and source records attributed to J. C. A. Tyrrell.

2 recordsLinked to original sources

arXiv2007

Optical carrier wave shocking: detection and dispersion

Carrier wave shocking is studied using the Pseudo-Spectral Spatial Domain (PSSD) technique. We describe the shock detection diagnostics necessary for this numerical study, and verify them against theoretical shocking predictions for the dispersionless case. These predictions show Carrier Envelope Phase (CEP) and pulse bandwidth sensitivity in the single-cycle regime. The flexible dispersion management offered by PSSD enables us to independently control the linear and nonlinear dispersion. Customized dispersion profiles allow us to analyze the development of both carrier self-steepening and shocks. The results exhibit a marked asymmetry between normal and anomalous dispersion, both in the limits of the shocking regime and in the (near) shocked pulse waveforms. Combining these insights, we offer some suggestions on how carrier shocking (or at least extreme self-steepening) might be realised experimentally.

physics.optics↗

arXiv2006

Phase sensitivity of perturbative nonlinear interactions

Despite the current concentration on phase control in few-cycle pulses, it emerges that there exists a wide class of nonlinear optical interactions in which the carrier phase is essentially irrelevant, even for the shortest pulse profiles. Most parametric processes and most perturbative processes fall into this category, although others such as above threshold ionization (ATI) do not. In an envelope approach, the carrier oscillations are not part of the problem because they are removed at the outset. When they are reinstated at the end of the calculation, one is free to include arbitrary phase shifts -- within certain constraints. In many cases the constraints are relatively weak, and it follows that a single envelope solution can be used with an infinite range of choices for the carrier phase.

physics.optics↗