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<export-example>
  <doc>
    <id>1891</id>
    <completedYear>2021</completedYear>
    <publishedYear/>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst>2002203</pageFirst>
    <pageLast>2002203</pageLast>
    <pageNumber/>
    <edition/>
    <issue>13</issue>
    <volume>9</volume>
    <type>article</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>2021-04-07</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Tunable Bulk Polymer Planar Bragg Gratings Electrified via Femtosecond Laser Reductive Sintering of CuO Nanoparticles</title>
    <abstract language="eng">This contribution demonstrates and discusses electrically tunable polymer planar Bragg gratings based on bulk cyclic olefin copolymers. A lithographic single-writing-step method and femtosecond laser reductive sintering of copper(II) oxide nanoparticles are subsequently employed in order to generate buried photonic structures and copper conducting paths on top of the polymer substrate. This way, the necessary number of process steps for fabricating a planar polymer-based electro-optical device is greatly reduced. The response of a fully electrified grating structure follows temperature changes, induced by the copper conducting path, with sensitivities up to −31 pm K−1. Dilatometric measurements show that the specimen's behavior is correlated to the situationally reduced thermal expansion of the bulk polymer substrate. In consequence, the tuning response of the photonic platform follows a second order polynomial, whereas a direct current of 30 mA, which correlates to a power consumption of 18.3 mW, leads to a local temperature increase and a residual Bragg wavelength shift of 19.6 K and −547 pm, respectively. Moreover, the outstanding flexibility of the proposed fabrication concept is underlined by demonstrating alternative conducting path geometries, whereas one of the additional designs is adapted to control the spectral width of the Bragg grating's reflection peak.</abstract>
    <parentTitle language="eng">Advanced Optical Materials</parentTitle>
    <identifier type="url">https://onlinelibrary.wiley.com/doi/10.1002/adom.202002203</identifier>
    <identifier type="doi">https://doi.org/10.1002/adom.202002203</identifier>
    <enrichment key="copyright">1</enrichment>
    <enrichment key="opus.source">publish</enrichment>
    <licence>Creative Commons - CC BY - Namensnennung 4.0 International</licence>
    <author>Stefan Kefer</author>
    <author>Kay Bischoff</author>
    <author>Gian-Luca Roth</author>
    <author>Julian Haubner</author>
    <author>Bernhard Schmauss</author>
    <author>Ralf Hellmann</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Bragg gratings</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>CuO nanoparticles</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>cyclic olefin copolymers</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>electro-optic tuning</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>integrated photonics</value>
    </subject>
    <subject>
      <language>deu</language>
      <type>swd</type>
      <value>Femtosekundenlaser</value>
    </subject>
    <subject>
      <language>deu</language>
      <type>swd</type>
      <value>Bragg-Reflektor</value>
    </subject>
    <collection role="forschungsschwerpunkte" number="">Intelligent Sensors and Signals</collection>
    <collection role="forschungsschwerpunkte" number="">Innovative Material Processing</collection>
    <collection role="forschungsschwerpunkte" number="">Material Testing &amp; Sensor Technology</collection>
    <file>https://opus4.kobv.de/opus4-h-ab/files/1891/ADOM_OPUS.pdf</file>
  </doc>
  <doc>
    <id>2084</id>
    <completedYear>2023</completedYear>
    <publishedYear/>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>conferenceobject</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>2023-03-21</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Towards Pressure Sensors Based on Polymer Planar Bragg Gratings</title>
    <abstract language="eng">While Bragg grating-based optical devices have shown promising performances for pressure sensing applications, their sensitivity, especially in the low-pressure regime, is unsatisfying and needs to be optimized by elaborate designs, such as cantilevers or other extrinsic mechanical transducers. This contribution demonstrates and discusses a novel concept for optical pressure sensors based on polymer planar Bragg gratings. Waveguide and Bragg grating are fabricated underneath the surface of a temperature-stable and humidity-insensitive cyclic olefin copolymer substrate by means of a femtosecond laser. Based on the employed direct-writing procedure, in combination with adaptive, in-situ beam shaping with a spatial light modulator, writing depth, i.e., location of the photonic structures within the substrate, as well as Bragg grating periodicity and positioning can be deliberately chosen. Afterwards, the polymer substrate is post-processed with a high-precision micro mill, so a diaphragm comprising the integrated photonic structures is generated. The resulting diaphragm exhibits a thickness of 300 µm and a diameter of 10 mm. Finally, the optical sensor is packaged and sealed to form an air-filled gas pocket underneath the diaphragm. Deformations of the diaphragm by external pressure changes translate to strain variations along the waveguide axis and thus perturb the Bragg grating period. This leads to changes in the grating’s wavelength of main reflection, which can be evaluated in order to quantify the relative external pressure. With this straightforward optical sensor concept, pressure sensitivities up to 39 pm kPa-1, within relative pressures ranges from  78 kPa to 372 kPa, are achieved.</abstract>
    <parentTitle language="eng">Organic Photonic Materials and Devices XXV</parentTitle>
    <identifier type="isbn">9781510659414</identifier>
    <identifier type="doi">10.1117/12.2648723</identifier>
    <enrichment key="copyright">1</enrichment>
    <enrichment key="opus.source">publish</enrichment>
    <enrichment key="opus.doi.autoCreate">false</enrichment>
    <enrichment key="opus.urn.autoCreate">false</enrichment>
    <licence>Keine Lizenz - es gilt das deutsche Urheberrecht</licence>
    <author>Stefan Kefer</author>
    <author>Natalie Pape</author>
    <author>Nikola Gries</author>
    <author>Gian-Luca Roth</author>
    <author>Bernhard Schmauss</author>
    <author>Ralf Hellmann</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Bragg grating</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>pressure sensor</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>integrated photonics</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>cyclic olefin copolymers</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>femtosecond laser</value>
    </subject>
    <subject>
      <language>deu</language>
      <type>swd</type>
      <value>Bragg-Reflektor</value>
    </subject>
    <subject>
      <language>deu</language>
      <type>swd</type>
      <value>Drucksensor</value>
    </subject>
    <collection role="institutes" number="">Angewandte Lasertechnik und Photonik (alp)</collection>
    <collection role="forschungsschwerpunkte" number="">Material Testing &amp; Sensor Technology</collection>
  </doc>
</export-example>
