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Generation and Coherent Control of Pulsed Quantum Frequency Combs
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Quantum Valley Hall Effect-Based Coupler with Continuously Tunable Transmission for Topological Information
Keita Funayama1, Kenichi Yatsugi1, Hiroya Tanaka1
1Toyota Central R&D Labs., Inc., Nagakute, Aichi, 480-1192, Japan.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|June 30, 2025
Summary
Researchers developed a tunable topological coupler for robust signal transfer. This breakthrough enables continuously adjustable transmission coefficients, advancing topological integrated circuits and communication systems.
Area of Science:
- Condensed matter physics
- Photonics
- Wave systems
Background:
- Topological insulators offer robust, unidirectional wave propagation.
- Tunable couplers are crucial for topological integrated circuits.
- Existing topological couplers lack continuously tunable transmission.
Purpose of the Study:
- To experimentally demonstrate a continuously tunable topological coupler.
- To show topological data transfer capabilities using the coupler.
Main Methods:
- Utilized quantum valley Hall effect-based waveguides in a four-port coupler.
- Investigated transmission coefficients within the bandgap.
- Demonstrated digital signal transfer using frequency shift keying modulation.
Main Results:
- Achieved continuously tunable transmission coefficients from one input to two output ports.
- Maintained topological protection, isolating the remaining port.
- Demonstrated high-fidelity digital signal transfer, approaching theoretical limits.
Conclusions:
- The developed coupler offers unprecedented tunability in topological wave systems.
- This work enables practical applications in topological data transfer and signal processing.
- Paves the way for advanced topological integrated circuits.
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