<?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>2026-04-30T00:42:35Z</responseDate><request verb="GetRecord" identifier="oai:uvadoc.uva.es:10324/40850" metadataPrefix="dim">https://uvadoc.uva.es/oai/request</request><GetRecord><record><header><identifier>oai:uvadoc.uva.es:10324/40850</identifier><datestamp>2025-02-21T12:28:50Z</datestamp><setSpec>com_10324_22154</setSpec><setSpec>com_10324_954</setSpec><setSpec>com_10324_894</setSpec><setSpec>col_10324_22155</setSpec></header><metadata><dim:dim xmlns:dim="http://www.dspace.org/xmlns/dspace/dim" xmlns:doc="http://www.lyncode.com/xoai" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.dspace.org/xmlns/dspace/dim http://www.dspace.org/schema/dim.xsd">
<dim:field mdschema="dc" element="contributor" qualifier="author" authority="fac7efc5b68bb0a9" confidence="600" orcid_id="0000-0003-3475-7696">Fassari, Silvestro</dim:field>
<dim:field mdschema="dc" element="contributor" qualifier="author" authority="de0f1e1891030a8b" confidence="500" orcid_id="0000-0001-8860-990X">Gadella Urquiza, Manuel</dim:field>
<dim:field mdschema="dc" element="contributor" qualifier="author" authority="894146a7-f7a6-4c03-9316-7859921dfedc" confidence="500" orcid_id="">Glasser, M. Lawrence</dim:field>
<dim:field mdschema="dc" element="contributor" qualifier="author" authority="b98486e4e688958d" confidence="500" orcid_id="0000-0002-2849-2647">Nieto Calzada, Luis Miguel</dim:field>
<dim:field mdschema="dc" element="contributor" qualifier="author" authority="2aeefb01-e399-4a96-bb59-7c413f6d0747" confidence="500" orcid_id="">Rinaldi, F.</dim:field>
<dim:field mdschema="dc" element="date" qualifier="accessioned">2020-05-16T10:36:23Z</dim:field>
<dim:field mdschema="dc" element="date" qualifier="available">2020-05-16T10:36:23Z</dim:field>
<dim:field mdschema="dc" element="date" qualifier="issued">2019</dim:field>
<dim:field mdschema="dc" element="identifier" qualifier="citation" lang="es">Physica Scripta, 2019, vol. 94</dim:field>
<dim:field mdschema="dc" element="identifier" qualifier="issn" lang="es">0031-8949</dim:field>
<dim:field mdschema="dc" element="identifier" qualifier="uri">http://uvadoc.uva.es/handle/10324/40850</dim:field>
<dim:field mdschema="dc" element="identifier" qualifier="doi" lang="es">10.1088/1402-4896/ab0589</dim:field>
<dim:field mdschema="dc" element="identifier" qualifier="publicationfirstpage" lang="es">055202</dim:field>
<dim:field mdschema="dc" element="identifier" qualifier="publicationissue" lang="es">5</dim:field>
<dim:field mdschema="dc" element="identifier" qualifier="publicationtitle" lang="es">Physica Scripta</dim:field>
<dim:field mdschema="dc" element="identifier" qualifier="publicationvolume" lang="es">94</dim:field>
<dim:field mdschema="dc" element="identifier" qualifier="essn" lang="es">1402-4896</dim:field>
<dim:field mdschema="dc" element="description" qualifier="abstract" lang="es">We study three solvable two-dimensional systems perturbed by a point interaction centered at the&#xd;
origin. The unperturbed systems are the isotropic harmonic oscillator, a square pyramidal&#xd;
potential and a combination thereof. We study the spectrum of the perturbed systems. We show&#xd;
that, while most eigenvalues are not affected by the point perturbation, a few of them are strongly&#xd;
perturbed. We show that for some values of one parameter, these perturbed eigenvalues may take&#xd;
lower values than the immediately lower eigenvalue, so that level crossings occur. These level&#xd;
crossings are studied in some detail.</dim:field>
<dim:field mdschema="dc" element="format" qualifier="mimetype" lang="es">application/pdf</dim:field>
<dim:field mdschema="dc" element="language" qualifier="iso" lang="es">spa</dim:field>
<dim:field mdschema="dc" element="rights" qualifier="accessRights" lang="es">info:eu-repo/semantics/openAccess</dim:field>
<dim:field mdschema="dc" element="title" lang="es">Spectral properties of the two-dimensional Schrödinger Hamiltonian with various solvable confinements in the presence of a central point perturbation</dim:field>
<dim:field mdschema="dc" element="type" lang="es">info:eu-repo/semantics/article</dim:field>
<dim:field mdschema="dc" element="type" qualifier="hasVersion" lang="es">info:eu-repo/semantics/publishedVersion</dim:field>
<dim:field mdschema="dc" element="peerreviewed" lang="es">SI</dim:field>
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