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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Long-range Cooper pair splitter with high entanglement production rate
Wei Chen1, D N Shi1, D Y Xing2
1College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
Scientific Reports
|January 6, 2015
Summary
This study introduces a novel method for creating entangled electron pairs using a supercurrent-driven superconductor-normal metal-superconductor junction, achieving high entanglement production rates and overcoming previous limitations.
Area of Science:
- Condensed matter physics
- Quantum information science
- Spintronics
Background:
- Cooper pairs in superconductors are a source of spin entanglement.
- Existing Cooper pair splitters have low efficiency and are limited by superconducting coherence length.
Purpose of the Study:
- To propose a long-range Cooper pair splitter with enhanced entanglement production.
- To overcome the limitations of existing Cooper pair splitter designs.
Main Methods:
- Utilizing a normal metal-superconductor-normal metal (NSN) junction.
- Driving a supercurrent in the superconductor (S) to modify its band gap.
- Leveraging enhanced crossed Andreev reflection (CAR) and suppressed elastic cotunneling.
Main Results:
- Achieved a high entanglement production rate close to saturation via inverse CAR.
- Demonstrated a long-range Cooper pair splitter independent of superconducting coherence length.
- Induced novel entangled electron states with equal energy levels, alongside conventional states.
Conclusions:
- The proposed NSN junction with a supercurrent offers a promising route for efficient, long-range spin entanglement generation.
- This method overcomes key limitations of current Cooper pair splitters.
- Opens new possibilities for quantum information processing and spintronic devices.
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