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Switching from normal to anomalous dispersion in photonic crystal with Raman gain defect
Optics Letters
|April 2, 2014
Summary
We show all-optical switching of light dispersion in a photonic crystal. The speed of Raman pulses can be controlled from slower-than-light to faster-than-light using pump field intensity.
Area of Science:
- Optics and Photonics
- Condensed Matter Physics
Background:
- Photonic crystals offer unique light manipulation properties.
- Defect layers within photonic crystals can introduce novel functionalities.
- Raman gain media enable light amplification and nonlinear optical effects.
Purpose of the Study:
- To investigate light propagation in a one-dimensional photonic crystal with a defect layer.
- To demonstrate all-optical control over dispersion properties.
- To analyze the group delay and group velocity of Raman pulses.
Main Methods:
- Theoretical analysis of light propagation through a 1D photonic crystal.
- Inclusion of a defect layer doped with a Raman gain medium.
- Numerical simulation of probe (Raman) pulse transmission.
- Investigation of the effect of pump field intensity on dispersion and group velocity.
Main Results:
- Demonstration of all-optically controlled switching between normal and anomalous dispersion.
- Observation of tunable group delay for transmitted Raman pulses.
- Control over Raman pulse group velocity, ranging from subluminal to superluminal speeds.
Conclusions:
- The proposed photonic crystal structure enables all-optical switching of dispersion.
- Pump field intensity is a key parameter for tuning the group velocity of Raman pulses.
- This research opens possibilities for novel optical switching and signal processing devices.
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