<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="static/style.xsl"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-06-28T15:19:04Z</responseDate><request verb="GetRecord" identifier="oai:docta.ucm.es:20.500.14352/33875" metadataPrefix="qdc">https://docta.ucm.es/rest/oai/request</request><GetRecord><record><header><identifier>oai:docta.ucm.es:20.500.14352/33875</identifier><datestamp>2023-08-25T10:59:43Z</datestamp><setSpec>com_20.500.14352_14</setSpec><setSpec>col_20.500.14352_15</setSpec></header><metadata><qdc:qualifieddc xmlns:qdc="http://dspace.org/qualifieddc/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:doc="http://www.lyncode.com/xoai" xsi:schemaLocation="http://purl.org/dc/elements/1.1/ http://dublincore.org/schemas/xmls/qdc/2006/01/06/dc.xsd http://purl.org/dc/terms/ http://dublincore.org/schemas/xmls/qdc/2006/01/06/dcterms.xsd http://dspace.org/qualifieddc/ http://www.ukoln.ac.uk/metadata/dcmi/xmlschema/qualifieddc.xsd">
   <dc:title>Unpolarized states and hidden polarization</dc:title>
   <dc:creator>Hoz Iglesias, Pablo de la</dc:creator>
   <dc:creator>Björk, G.</dc:creator>
   <dc:creator>Klimov, Andrei B.</dc:creator>
   <dc:creator>Leuchs, Gerd</dc:creator>
   <dc:creator>Sánchez Soto, Luis Lorenzo</dc:creator>
   <dcterms:abstract>We capitalize on a multipolar expansion of the polarization density matrix, in which multipoles appear as successive moments of the Stokes variables. When all the multipoles up to a given order K vanish, we can properly say that the state isKth-order unpolarized, as it lacks of polarization information to that order. First-order unpolarized states coincide with the corresponding classical ones, whereas unpolarized to any order tally with the quantum notion of fully invariant states. In between these two extreme cases, there is a rich variety of situations that are explored here. The existence of hidden polarization emerges in a natural way in this context.</dcterms:abstract>
   <dcterms:dateAccepted>2023-06-19T13:29:58Z</dcterms:dateAccepted>
   <dcterms:available>2023-06-19T13:29:58Z</dcterms:available>
   <dcterms:created>2023-06-19T13:29:58Z</dcterms:created>
   <dcterms:issued>2014-10-15</dcterms:issued>
   <dc:type>journal article</dc:type>
   <dc:identifier>https://hdl.handle.net/20.500.14352/33875</dc:identifier>
   <dc:identifier>1050-2947</dc:identifier>
   <dc:identifier>10.1103/PhysRevA.90.043826</dc:identifier>
   <dc:language>eng</dc:language>
   <dc:relation>621-2011-4575</dc:relation>
   <dc:relation>106525</dc:relation>
   <dc:relation>FIS2011-26786</dc:relation>
   <dc:rights>open access</dc:rights>
   <dc:publisher>American Physical Society</dc:publisher>
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