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Topologically Protected Valley-Dependent Quantum Photonic Circuits
Yang Chen1,2, Xin-Tao He3, Yu-Jie Cheng1,2
1Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, China.
Physical Review Letters
|June 25, 2021
Summary
This study introduces topological photonic beam splitters for robust quantum information processing. These devices enable on-chip quantum interference and the creation of entangled states, paving the way for advanced photonic circuits.
Area of Science:
- * Photonics and Quantum Information Science
- * Condensed Matter Physics and Materials Science
Background:
- * Topological photonics offers robust light transport for integrated optics and quantum applications.
- * Valley-contrasting physics in photonic structures enables valley-related edge states and wave division.
- * On-chip quantum information processing requires advanced photonic devices for manipulating quantum states.
Purpose of the Study:
- * To design and fabricate nanophotonic topological harpoon-shaped beam splitters (HSBSs).
- * To demonstrate the first on-chip valley-dependent quantum information processing.
- * To explore the potential of photonic valley states in quantum circuits.
Main Methods:
- * Fabrication of nanophotonic topological harpoon-shaped beam splitters (HSBSs) using 120-deg-bending interfaces.
- * Demonstration of two-photon quantum interference (Hong-Ou-Mandel interference) with a 50/50 HSBS.
- * Cascading HSBSs to build a simple quantum photonic circuit and generate path-entangled states.
Main Results:
- * Achieved high-visibility Hong-Ou-Mandel interference (0.956±0.006) using a 50/50 HSBS.
- * Successfully demonstrated a simple quantum photonic circuit by cascading HSBSs.
- * Generated a path-entangled state using the developed topological photonic components.
Conclusions:
- * Photonic valley states can be effectively utilized for quantum information processing.
- * Valley-dependent photonic topological insulators offer a novel approach for on-chip quantum information processing.
- * The developed HSBSs provide a new method for realizing complex quantum circuits.
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