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Optimization of adiabaticity in coupled-waveguide devices using shortcuts to adiabaticity
Optics Letters
|October 30, 2015
Summary
We developed a new technique for adiabatic coupled-waveguide devices that ensures 100% efficiency at any length. This method uses shortcuts-to-adiabaticity for precise system control and robust performance against variations.
Area of Science:
- Photonics and Waveguide Technology
- Quantum Control and Adiabatic Dynamics
Background:
- Conventional adiabatic coupled-waveguide devices achieve high efficiency but are restricted to specific lengths.
- Optimizing adiabaticity alone does not guarantee 100% efficiency across all device lengths.
Purpose of the Study:
- To develop a technique for designing adiabatic coupled-waveguide devices with guaranteed 100% coupling/conversion efficiency at any physically realizable length.
- To enhance the robustness of these devices against wavelength and fabrication variations.
Main Methods:
- Utilizing the shortcuts-to-adiabaticity technique to accurately represent the system state.
- Engineering system evolution to closely mimic the ideal adiabatic state.
- Deriving smooth parameters for coupled-waveguide device design.
Main Results:
- A simple technique was established for optimizing device adiabaticity and ensuring 100% efficiency.
- The derived parameters provide robustness against wavelength and fabrication variations.
- Beam propagation simulations verified the effectiveness of the proposed device design.
Conclusions:
- The shortcuts-to-adiabaticity technique offers a powerful approach for designing efficient and robust adiabatic coupled-waveguide devices.
- This method overcomes the length limitations of conventional designs, enabling universal 100% efficiency.
- The proposed devices demonstrate practical applicability due to their resilience to real-world variations.
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