skip to main content

Search for: All records

Creators/Authors contains: "Sevison, Gary A."

Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher. Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?

Some links on this page may take you to non-federal websites. Their policies may differ from this site.

  1. For active beam manipulation devices, such as those based on liquid crystals, phase-change materials, or electro-optic materials, measuring accumulated phase of the light passing through a layer of the material is imperative to understand the functionality of the overall device. In this work we discuss a way of measuring the phase accumulation through a switched layer of Ge2Sb2Te5, which is seeing rapid use as means to high speed dynamic reconfiguration of free space light. Utilizing an interferometer in the switching setup and modulating the phase of one arm, the intensity of a probe beam can be captured and phase data pulled from it. Simulations were used to discover the connection between the intensity modulations and the phase information. The technique was tested experimentally and it was found that within error, the measurement was robust and repeatable.

    more » « less
  2. We created a system for the characterization of Ge2Sb2Te5 starting with a 1550 nm CW laser and utilizing second harmonic generation through a PPLN crystal in order to achieve full pulse control at 775 nm. 
    more » « less
  3. We present an advancement towards high speed (sub ps) phase change material based spatial light modulators by electrically addressing single pixels with high-speed optical monitoring at 1550nm light. 
    more » « less
  4. null (Ed.)
  5. By doping Ge2Sb2Te5 phase change material with tungsten,we produce material with improved electrical properties while simultaneously maintaining the optical contrast necessary for light modulation and switching. 
    more » « less
  6. We experimentally demonstrate free-space phase change of Germanium Antimony Telluride (GST), switching between the amorphous and hexagonal crystalline states utilizing telecom-band laser pulses. 
    more » « less