Localization-delocalization wavepacket transition in Pythagorean aperiodic potentials

We introduce a composite optical lattice created by two mutually rotated square patterns and allowing observation of continuous transformation between incommensurate and completely periodic structures upon variation of the rotation angle θ. Such lattices acquire periodicity only for rotation angles...

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Detalles Bibliográficos
Autores: Huang, Changming, Ye, Fangwei, Chen, Xianfeng, Kartashov, Yaroslav V., Konotop, Vladimir V., Torner, Lluis
Tipo de recurso: artículo
Fecha de publicación:2016
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/98313
Acceso en línea:https://hdl.handle.net/2117/98313
Access Level:acceso abierto
Palabra clave:Optical lattices
wavepacket transition
Fotònica
Àrees temàtiques de la UPC::Física
Descripción
Sumario:We introduce a composite optical lattice created by two mutually rotated square patterns and allowing observation of continuous transformation between incommensurate and completely periodic structures upon variation of the rotation angle θ. Such lattices acquire periodicity only for rotation angles cosθ=a/c, sinθ=b/c, set by Pythagorean triples of natural numbers (a, b, c). While linear eigenmodes supported by lattices associated with Pythagorean triples are always extended, composite patterns generated for intermediate rotation angles allow observation of the localizationdelocalization transition of eigenmodes upon modification of the relative strength of two sublattices forming the composite pattern. Sharp delocalization of supported modes for certain θ values can be used for visualization of Pythagorean triples. The effects predicted here are general and also take place in composite structures generated by two rotated hexagonal lattices