Anderson Localization of Light in the Presence of Non-linear Effects

Lade...
Vorschaubild
Dateien
Dissertation_Buehrer.pdf
Dissertation_Buehrer.pdfGröße: 5.71 MBDownloads: 279
Datum
2012
Herausgeber:innen
Kontakt
ISSN der Zeitschrift
Electronic ISSN
ISBN
Bibliografische Daten
Verlag
Schriftenreihe
Auflagebezeichnung
DOI (zitierfähiger Link)
ArXiv-ID
Internationale Patentnummer
Angaben zur Forschungsförderung
Projekt
Open Access-Veröffentlichung
Open Access Green
Sammlungen
Core Facility der Universität Konstanz
Gesperrt bis
Titel in einer weiteren Sprache
Publikationstyp
Dissertation
Publikationsstatus
Published
Erschienen in
Zusammenfassung

The goal of the thesis presented here, was to further investigate the findings of Dr. Störzer in order to prove the wave nature of Anderson Localization. For this, two different approaches and setups were used.



The first was a single photon counting Time-of-Flight setup, but with increased laser power and less noise in the detection part, where band pass filters were used as a crude spectrometer for analysing the spectral distribution of the photons travelling through highly turbid random media consisting of TiO2 particles. A spectral broadening of the light travelling through such samples could be measured, caused by the non-linear response of TiO2. The amount of wave-length shifted photons could be determined as being dependent on the turbidity kl*. Given, that the energy density is high in interference loops causing Anderson localization, which is a common picture for explaining the effect, one can show using the non-linearity of TiO2, that these interference loops become more and more populated when the turbidity of the sample is increased (i.e. kl* is lowered). We varied the turbidity with samples of different TiO2 particles as well as with the same sample, but varying the wavelength of the incident light. Both of these approaches yield the same changes in dependence of kl*. This excludes sample-intrinsic properties (apart from the non-linearity) as being the cause for different responses.



Secondly, a new setup with an ultrafast gatable high rate image intensifier and a 16bit-CCD camera was built, which made it possible to directly observe the time evolution of the exiting photon cloud emerging from a highly scattering sample. As theoretical predictions suggest, Anderson localization should be detectable in the time evolution of the lateral confinement of the exiting photonic cloud. We could demonstrate that this is generally correct using a purely diffusive and several non-diffusive samples. Furthermore, we could show that the predicted time evolution of the lateral width sigma^2 proportional to the squareroot of t of the photonic cloud is not observed but rather, that the width behaves linearly, as one would intuitively expect from diffusion theory. Again, by variation of the incident wavelength we could show, that the localizing behaviour is not sample intrinsic but kl*-dependent, as expected for the Anderson transition.

Zusammenfassung in einer weiteren Sprache
Fachgebiet (DDC)
530 Physik
Schlagwörter
Anderson Localization, Light, non-linear, 3D
Konferenz
Rezension
undefined / . - undefined, undefined
Forschungsvorhaben
Organisationseinheiten
Zeitschriftenheft
Datensätze
Zitieren
ISO 690BÜHRER, Wolfgang, 2012. Anderson Localization of Light in the Presence of Non-linear Effects [Dissertation]. Konstanz: University of Konstanz
BibTex
@phdthesis{Buhrer2012Ander-20787,
  year={2012},
  title={Anderson Localization of Light in the Presence of Non-linear Effects},
  author={Bührer, Wolfgang},
  address={Konstanz},
  school={Universität Konstanz}
}
RDF
<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/123456789/20787">
    <dc:date rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2012-10-29T07:57:00Z</dc:date>
    <dcterms:abstract xml:lang="eng">The goal of the thesis presented here, was to further investigate the findings of Dr. Störzer in order to prove the wave nature of Anderson Localization. For this, two different approaches and setups were used.&lt;br /&gt;&lt;br /&gt;&lt;br /&gt;&lt;br /&gt;The first was a single photon counting Time-of-Flight setup, but with increased laser power and less noise in the detection part, where band pass filters were used as a crude spectrometer for analysing the spectral distribution of the photons travelling through highly turbid random media consisting of TiO2 particles. A spectral broadening of the light travelling through such samples could be measured, caused by the non-linear response of TiO2. The amount of wave-length shifted photons could be determined as being dependent on the turbidity kl*. Given, that the energy density is high in interference loops causing Anderson localization, which is a common picture for explaining the effect, one can show using the non-linearity of TiO2, that these interference loops become more and more populated when the turbidity of the sample is increased (i.e. kl* is lowered). We varied the turbidity with samples of different TiO2 particles as well as with the same sample, but varying the wavelength of the incident light. Both of these approaches yield the same changes in dependence of kl*. This excludes sample-intrinsic properties (apart from the non-linearity) as being the cause for different responses.&lt;br /&gt;&lt;br /&gt;&lt;br /&gt;&lt;br /&gt;Secondly, a new setup with an ultrafast gatable high rate image intensifier and a 16bit-CCD camera was built, which made it possible to directly observe the time evolution of the exiting photon cloud emerging from a highly scattering sample. As theoretical predictions suggest, Anderson localization should be detectable in the time evolution of the lateral confinement of the exiting photonic cloud. We could demonstrate that this is generally correct using a purely diffusive and several non-diffusive samples. Furthermore, we could show that the predicted time evolution of the lateral width sigma^2 proportional to the squareroot of t of the photonic cloud is not observed but rather, that the width behaves linearly, as one would intuitively expect from diffusion theory. Again, by variation of the incident wavelength we could show, that the localizing behaviour is not sample intrinsic but kl*-dependent, as expected for the Anderson transition.</dcterms:abstract>
    <void:sparqlEndpoint rdf:resource="http://localhost/fuseki/dspace/sparql"/>
    <dspace:isPartOfCollection rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/41"/>
    <dspace:hasBitstream rdf:resource="https://kops.uni-konstanz.de/bitstream/123456789/20787/2/Dissertation_Buehrer.pdf"/>
    <dcterms:available rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2012-10-29T07:57:00Z</dcterms:available>
    <dcterms:title>Anderson Localization of Light in the Presence of Non-linear Effects</dcterms:title>
    <bibo:uri rdf:resource="http://kops.uni-konstanz.de/handle/123456789/20787"/>
    <dcterms:rights rdf:resource="https://rightsstatements.org/page/InC/1.0/"/>
    <dc:creator>Bührer, Wolfgang</dc:creator>
    <dcterms:hasPart rdf:resource="https://kops.uni-konstanz.de/bitstream/123456789/20787/2/Dissertation_Buehrer.pdf"/>
    <dcterms:isPartOf rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/41"/>
    <dc:language>eng</dc:language>
    <dcterms:issued>2012</dcterms:issued>
    <dc:rights>terms-of-use</dc:rights>
    <dc:contributor>Bührer, Wolfgang</dc:contributor>
    <foaf:homepage rdf:resource="http://localhost:8080/"/>
  </rdf:Description>
</rdf:RDF>
Interner Vermerk
xmlui.Submission.submit.DescribeStep.inputForms.label.kops_note_fromSubmitter
Kontakt
URL der Originalveröffentl.
Prüfdatum der URL
Prüfungsdatum der Dissertation
October 24, 2012
Finanzierungsart
Kommentar zur Publikation
Allianzlizenz
Corresponding Authors der Uni Konstanz vorhanden
Internationale Co-Autor:innen
Universitätsbibliographie
Begutachtet
Diese Publikation teilen