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14:18
Automation of Mode Locking in a Nonlinear Polarization Rotation Fiber Laser through Output Polarization Measurements
Published on: February 28, 2016
Orbital angular momentum generation and mode transformation with high efficiency using forked polarization gratings
Yanming Li1, Jihwan Kim, Michael J Escuti
1Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695, USA.
Applied Optics
|December 5, 2012
Summary
We developed a novel optical element, the forked polarization grating (FPG), that efficiently generates and transforms light
Area of Science:
- Optics and Photonics
- Liquid Crystal Devices
- Light Manipulation
Background:
- Orbital angular momentum (OAM) of light offers unique properties for advanced applications.
- Efficient generation and control of OAM modes are crucial for optical technologies.
Purpose of the Study:
- To introduce a novel forked polarization grating (FPG) for efficient OAM generation and mode transformation.
- To demonstrate the FPG's capability to control OAM modes with high efficiency and polarization tunability.
Main Methods:
- Fabrication of static and switchable liquid crystal-based FPGs utilizing Pancharatnam-Berry phase.
- Theoretical and experimental validation of OAM generation and mode conversion.
- Characterization of diffraction efficiency and polarization control.
Main Results:
- Achieved high theoretical (100%) and experimental (∼95%) diffraction efficiency for OAM generation/transformation.
- Demonstrated polarization-controllable power splitting between output OAM modes (0% to 100%).
- Successfully fabricated switchable FPGs with >92% conversion efficiency at 633 nm.
Conclusions:
- FPGs provide a compact, efficient, and versatile platform for OAM manipulation across various wavelengths.
- These elements are ideal for applications requiring precise OAM control, such as optical trapping and high-capacity information transmission.
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