LMI Seminar: Probing borders between geometry and physics with micro-billiard lasers

Abstract:

The billiard paradigm is being widely studied in nonlinear dynamics and mathematical physics as a test-bed onto fundamental issues pertaining to quantum mechanics, wave physics, and both classical and quantum chaos. Among these, the elusive border between wave and geometric optics on the one hand, and between quantum and classical mechanics on the other, remain a challenge with deep analogies between them, which can be experimentally probed in billiard-like physical systems. We will show the relevance in this context of micro-billiard shaped lasers, thanks to new experimental and fabrication advances in the realm of polymer based photonics at the micron and nanometer scales.

Closed orbits viewed as spatial geodesics folded within a confining contour, are playing a central role in this field, which can be connected to a distributed electromagnetic models via semi-classical physics concepts. Particular attention will be paid to systematic theoretical and experimental investigations of triangular cavities in relation with their symmetry types, full elucidation of the remarkable emission properties of square cavities close to the lasing threshold and preliminary explorations onto the unchartered field of 3-D micro-billiards.

This work is being performed at LPQM/ENS Cachan/UPS, together with Clément Lafargue (ex-Ph.D. student), Stefan Bittner (postdoctoral fellow) and Mélanie Lebental (assistant professor) in collaboration with Eugene Bogomolny from LPTMS (University Paris-Saclay and CNRS).