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Published on: February 25, 2017
Photocurrent response from photonic crystal defect modes
Stephan Schartner1, Michele Nobile, Werner Schrenk
1Center for Micro- and Nanostructures, Vienna University of Technology, Floragasse 7, 1040 Vienna, Austria. Stephan.Schartner@tuwien.ac.at
Optics Express
|June 11, 2008
Summary
Researchers studied optical defect modes in photonic crystals using quantum well photodetectors. They observed enhanced photocurrent due to light in-coupling at defect sites, correlating mode frequencies with defect geometry.
Area of Science:
- Optoelectronics
- Photonics
- Condensed Matter Physics
Background:
- Photonic crystals offer unique light manipulation properties.
- Defect modes in photonic crystals can localize light.
- Quantum well photodetectors are sensitive to optical signals.
Purpose of the Study:
- Investigate optical defect modes in a 2D photonic crystal.
- Understand the relationship between defect geometry and mode frequencies.
- Correlate photocurrent enhancement with defect mode excitation.
Main Methods:
- Fabrication of a quantum well intersubband photodetector.
- Integration of the photodetector into a 2D photonic crystal.
- Characterization of spectral photocurrent.
- Systematic variation of defect geometry.
- Comparison with theoretical simulations.
Main Results:
- Observed localized optical defect modes.
- Demonstrated local enhancement in spectral photocurrent.
- Attributed photocurrent enhancement to increased in-coupling of surface incident light.
- Tracked mode frequencies as a function of defect geometry.
- Found good agreement between experimental results and simulations.
Conclusions:
- The study successfully demonstrates the use of photodetectors to probe optical defect modes in photonic crystals.
- Photocurrent enhancement serves as a direct measure of defect mode excitation and light in-coupling.
- The findings provide valuable insights into the design and application of photonic crystal devices.
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