Pamela L. Overfelt | Searcharxiv

arXiv2006

Subwavelength fractional Talbot effect in layered heterostructures of composite metamaterials

We demonstrate that under certain conditions, fractional Talbot revivals can occur in heterostructures of composite metamaterials, such as multilayer positive and negative index media, metallodielectric stacks, and one-dimensional dielectric photonic crystals. Most importantly, without using the paraxial approximation we obtain Talbot images for the feature sizes of transverse patterns smaller than the illumination wavelength. A general expression for the Talbot distance in such structures is derived, and the conditions favorable for observing Talbot effects in layered heterostructures is discussed.

physics.optics↗

arXiv2005

Transparent photonic band in metallodielectric nanostructures

Under certain conditions, a transparent photonic band can be designed into a one-dimensional metallodielectric nanofilm structure. Unlike conventional pass bands in photonic crystals, where the finite thickness of the structure affects the transmission of electromagnetic fields having frequency within the pass band, the properties of the transparent band are almost unaffected by the finite thickness of the structure. In other words, an incident field at a frequency within the transparent band exhibits 100% transmission independent of the number of periods of the structure. The transparent photonic band corresponds to excitation of pure eigenstate modes across the entire Bloch band in structures possessing mirror symmetry. The conditions to create these modes and thereby to lead to a totally transparent band phenomenon are discussed.

physics.optics↗