Mesoscopic self-collimation : beyond the high symmetry constraint
Résumé
Self-Collimation (SC) [1] in Photonic Crystals (PhC) represents a new mean for achieving structure-less light confinement in optical devices - no typical confining mechanisms, like bandgaps or index guiding, being actually involved. However, it reveals to be quite constrictive in terms of degrees of freedom left for design. Recently, mesoscopic SC (MSC) in mesoscopic PhC (MPCs) [2] has loosen this design constrictiveness, extending the application range especially thanks to the possibility to combine SC with other desired optical features as slow light, controlled reflectivity [3] and microcavities with planar reflectors [4]. This contribution aims to achieve MSC even in arbitrary directions. Moreover this allows to obtain MSC even below the light line, neatly addressing the main drawback of the MPCs: out of plane losses due to the long mesoscopic period.