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Rotated chirped volume Bragg gratings for compact spectral analysis
Optics Letters
|March 1, 2023
Summary
We developed a new rotated chirped volume Bragg grating (r-CBG) that spatially resolves light spectra compactly. This innovation reduces device size for a given bandwidth, enabling ultracompact spectrometers and pulse modulators.
Area of Science:
- Optics and Photonics
- Spectroscopy
- Optical Engineering
Background:
- Conventional chirped volume Bragg gratings (CBGs) require larger footprints to increase spectral bandwidth.
- Existing CBGs often necessitate additional free-space propagation or collimation for spectral analysis.
- There is a need for compact, efficient optical components for spectral resolution.
Purpose of the Study:
- To introduce a novel optical component, the rotated chirped volume Bragg grating (r-CBG).
- To demonstrate that r-CBGs can spatially resolve spectra in a compact footprint.
- To show that r-CBGs enable ultracompact spectrometers and pulse modulators.
Main Methods:
- Design and fabrication of a rotated chirped volume Bragg grating (r-CBG).
- Characterization of the r-CBG's spectral resolution across multiple spectral windows.
- Experimental demonstration of cascaded r-CBGs for spectral resolution and recombination.
Main Results:
- The r-CBG spatially resolves spectra of normally incident light without collimation.
- Rotating the Bragg structure decouples device length and width, reducing footprint for a given bandwidth.
- Cascaded r-CBGs successfully resolved and recombined spectral components.
Conclusions:
- The r-CBG is a novel optical component offering compact spectral resolution.
- This technology significantly reduces the footprint of chirped volume Bragg gratings.
- r-CBGs hold promise for developing next-generation ultracompact spectrometers and pulse modulators.
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