@article{Kobler1993Biqua-8968,
  year={1993},
  doi={10.1007/BF01320511},
  title={Biquadratic exchange and critical behaviour in the diluted antiferromagnet Eu-Sr-Te},
  number={4},
  volume={92},
  journal={Zeitschrift für Physik / B},
  pages={475--487},
  author={Köbler, Ulrich and Apfelstedt, I. and Fischer, K. and Zinn, W. and Scheer, Elke and Wosnitza, Jochen and Löhneysen, Hilbert von and Brückel, Thomas}
}

<rdf:RDF
    xmlns:dcterms="http://purl.org/dc/terms/"
    xmlns:dc="http://purl.org/dc/elements/1.1/"
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:bibo="http://purl.org/ontology/bibo/"
    xmlns:dspace="http://digital-repositories.org/ontologies/dspace/0.1.0#"
    xmlns:foaf="http://xmlns.com/foaf/0.1/"
    xmlns:void="http://rdfs.org/ns/void#"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema#" > 
  <rdf:Description rdf:about="https://kops.uni-konstanz.de/server/rdf/resource/123456789/8968">
    <dc:creator>Köbler, Ulrich</dc:creator>
    <dcterms:title>Biquadratic exchange and critical behaviour in the diluted antiferromagnet Eu-Sr-Te</dcterms:title>
    <void:sparqlEndpoint rdf:resource="http://localhost/fuseki/dspace/sparql"/>
    <dc:creator>Fischer, K.</dc:creator>
    <dc:contributor>Löhneysen, Hilbert von</dc:contributor>
    <dc:format>application/pdf</dc:format>
    <dc:creator>Scheer, Elke</dc:creator>
    <dcterms:available rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2011-03-24T17:52:29Z</dcterms:available>
    <dc:rights>Attribution-NonCommercial-NoDerivs 2.0 Generic</dc:rights>
    <dc:contributor>Wosnitza, Jochen</dc:contributor>
    <dc:contributor>Brückel, Thomas</dc:contributor>
    <dc:contributor>Fischer, K.</dc:contributor>
    <dc:creator>Zinn, W.</dc:creator>
    <dc:date rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2011-03-24T17:52:29Z</dc:date>
    <dspace:hasBitstream rdf:resource="https://kops.uni-konstanz.de/bitstream/123456789/8968/1/biquadratic_exchange_and_critical_behaviour_in_the.pdf"/>
    <dcterms:abstract xml:lang="deu">Magnetization, specific heat, magnetocaloric effect, and neutron diffraction measurements have been performed in order to better understand the magnetic interactions and phase transitions in the diluted antiferromagnetic system EuxSrl_xTe. Due to the low N6el temperature of TN=9.8 K and the associated small critical field of Be(T= 0)= 7.5 T, EuTe provides the opportunity to change the angle between the antiferromagnetic moments continuously between 180 ~ and 0 ~ by applying a magnetic field and allows thus to probe the type of the magnetic interaction. It is found that in addition to the common bilinear Heisenberg exchange mechanism there is evidence for a small biquadratic exchange term, which has important consequences on the critical behaviour of EuxSr~_xTe. In the case of EuTe the biquadratic exchange supports the antiferromagnetic order, such that virtually no anisotropy exists and this restricts the antiferromagnetic (AF) to spin-flop (SF) transition to B0 = 0. On dilution with strontium, the biquadratic interaction decreases strongly and changes its sign at x~0.83 thus favouring the perpendicular moment orientation. This acts like an anisotropy on the dominating antiferromagnetic bilinear interaction and shifts the AF-SF phase line to finite fields which reach values of 0.3 T for T~ 0. No bicritieal behaviour is observed, but instead, the SF phase is the state of lowest energy in a small temperature interval below TN. The critical exponent ~(x) of the specific heat decreases in a non-linear way with dilution starting from a large positive value for EuTe. e(x) is close to the Heisenberg value -0.12 near x~0.83 where the biquadratic interaction is zero. The same applies for the exponent fl of the sublattice magnetization.</dcterms:abstract>
    <dc:creator>Brückel, Thomas</dc:creator>
    <dcterms:bibliographicCitation>First publ. in: Zeitschrift für Physik / B, 92 (1993), 4, pp. 475-487</dcterms:bibliographicCitation>
    <dc:contributor>Zinn, W.</dc:contributor>
    <dc:creator>Löhneysen, Hilbert von</dc:creator>
    <dspace:isPartOfCollection rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/41"/>
    <bibo:uri rdf:resource="http://kops.uni-konstanz.de/handle/123456789/8968"/>
    <dc:creator>Wosnitza, Jochen</dc:creator>
    <dc:contributor>Köbler, Ulrich</dc:contributor>
    <dc:contributor>Scheer, Elke</dc:contributor>
    <foaf:homepage rdf:resource="http://localhost:8080/"/>
    <dcterms:hasPart rdf:resource="https://kops.uni-konstanz.de/bitstream/123456789/8968/1/biquadratic_exchange_and_critical_behaviour_in_the.pdf"/>
    <dc:contributor>Apfelstedt, I.</dc:contributor>
    <dcterms:issued>1993</dcterms:issued>
    <dc:language>eng</dc:language>
    <dc:creator>Apfelstedt, I.</dc:creator>
    <dcterms:isPartOf rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/41"/>
    <dcterms:rights rdf:resource="http://creativecommons.org/licenses/by-nc-nd/2.0/"/>
  </rdf:Description>
</rdf:RDF>