Geometric filtering effect in expanding Bose-Einstein condensate shells

A shell-shaped Bose-Einstein condensate released from its confinement expands radially both outward and inward, displaying a self-interference pattern characterized by a density peak surrounded by a halo. Here we analyze how an external imprinting or the thermal fluctuations of the condensate phase...

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Detalles Bibliográficos
Autores: Tononi, Andrea|||0000-0002-0023-3977, Lewenstein, Maciej, Santos, Luis
Tipo de recurso: artículo
Fecha de publicación:2025
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:2117/451835
Acceso en línea:https://hdl.handle.net/2117/451835
https://dx.doi.org/10.1103/6zqw-tysq
Access Level:acceso abierto
Palabra clave:Bose-Einstein condensates
Atoms
Bose gases
Superfluids
Ultracold gases
Àrees temàtiques de la UPC::Física::Física molecular
Descripción
Sumario:A shell-shaped Bose-Einstein condensate released from its confinement expands radially both outward and inward, displaying a self-interference pattern characterized by a density peak surrounded by a halo. Here we analyze how an external imprinting or the thermal fluctuations of the condensate phase influence this expansion. In both cases we find that the curved geometry filters the imploding finite angular-momentum modes via a radial centrifugal potential, so that only the condensate state can reach the origin and form the central peak. As a consequence, we observe a pronounced dependence of the central density on the imprinting strength and on temperature. This geometric filtering effect characterizes the free expansion of curved atomic gases in contrast with flat counterparts, it is easily observable in the available experimental platforms and enables two-dimensional shells thermometry via simple absorption-imaging techniques.