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Tunable spectral shifts and spectral switches by controllable phase modulation
Mohammad Amiri1, Mohammad Taghi Tavassoly, Hajir Dolatkhah
1Physics Department, Bu-Ali Sina University, Hamedan 65174, Iran. amiri@iasbs.ac.ir
Optics Express
|December 18, 2010
Summary
This study introduces a simple method for spectral switches using a one-dimensional phase step. Varying the step height controls light properties for potential use in information encoding.
Area of Science:
- Optics and Photonics
- Information Technology
Background:
- Spectral switches are crucial for optical signal processing.
- Existing methods often require complex light source modulation.
Purpose of the Study:
- To present a novel and simple method for achieving spectral switches.
- To demonstrate the feasibility of controlling spectral properties via phase modulation.
Main Methods:
- Utilizing a one-dimensional phase step to control the phase of a diffracted light field.
- Analyzing the spectral profile of a spatially coherent incident beam.
- Deriving analytical expressions and performing numerical simulations.
- Experimental validation of the proposed method.
Main Results:
- Spectral switches are achieved by simply adjusting the height of the phase step.
- The method does not require modulation of the light source properties.
- Critical step heights were identified for spectral switching.
- Experimental results confirmed the analytical predictions.
Conclusions:
- The proposed method offers a flexible and easily implementable approach to spectral switching.
- The technique demonstrates a very short response time.
- This method is suitable for applications in information encoding and transmission.
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