Related Experiment Video
Updated: May 21, 2025
12:14
The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
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Cascaded-mode interferometers: Spectral shape and linewidth engineering
Jinsheng Lu1, Ileana-Cristina Benea-Chelmus1,2, Vincent Ginis1,3
1Harvard John A. Paulson School of Engineering and Applied Sciences, 9 Oxford Street, Cambridge, MA 02138, USA.
Science Advances
|March 19, 2025
Summary
This study introduces a novel waveguide interferometer for arbitrary spectral shaping. It enables precise control over spectral properties like linewidth and free spectral range for advanced optical applications.
Area of Science:
- Optics and Photonics
- Quantum Mechanics
- Laser Physics
Background:
- Interferometers are crucial for optical field manipulation in metrology and sensing.
- Conventional Mach-Zehnder interferometers have limitations in spectral engineering due to sinusoidal output.
- Advanced spectral shaping is needed for filtering, routing, and multiplexing applications.
Purpose of the Study:
- To propose a novel framework for arbitrary spectral shaping using multimode interference.
- To achieve compact and versatile spectral engineering capabilities.
- To demonstrate independent control over spectral linewidth and free spectral range.
Main Methods:
- Utilizing interference of multiple transverse modes within a single multimode waveguide.
- Employing designed corrugated gratings for efficient mode coupling and energy exchange.
- Theoretical modeling and experimental validation of the proposed framework.
Main Results:
- Demonstration of arbitrary spectral shapes with independently tunable linewidth and free spectral range.
- Successful application to various orthogonal modes (order, polarization, angular momentum).
- Experimental validation of the compact multimode waveguide interferometer concept.
Conclusions:
- The proposed multimode interference framework offers a powerful new method for spectral shaping.
- This technique provides enhanced flexibility and compactness compared to conventional interferometers.
- Potential applications include advanced sensing, calibration, metrology, and optical computing.
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