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Crossed Andreev reflection in normal-superconductor-normal junction based on Kekulé-Y patterned graphene
Xue-Si Li1, Dong-Yan Liu1, Zhao Jin2
1Normal College, Shenyang University, Shenyang 110044, People's Republic of China.
Summary
This study explores crossed Andreev reflection (CAR) in graphene heterojunctions. Enhanced CAR is observed in nSp junctions, particularly within the single Dirac cone phase.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Phenomena
Background:
- Normal metal-superconductor-normal metal (NSN) heterojunctions are crucial for studying quantum effects.
- Kekulé-Y patterned graphene offers unique electronic properties for novel device applications.
- Crossed Andreev reflection (CAR) is a key phenomenon in superconducting heterostructures.
Purpose of the Study:
- To theoretically investigate the crossed Andreev reflection (CAR) in NSN heterojunctions based on Kekulé-Y patterned graphene.
- To compare CAR efficiency in nSn and nSp doping configurations.
- To analyze the influence of incident angle, energy, superconductor length, and pseudospin-valley coupling on conductance.
Main Methods:
- Theoretical modeling of electron transport in graphene-based NSN heterojunctions.
- Analysis of band structures and transmission probabilities.
- Numerical evaluation of conductance under varying physical parameters.
Main Results:
- Enhanced CAR is significantly more probable in nSp junctions compared to nSn junctions.
- Almost perfect CAR is achieved over a broad range of incident angles in the single Dirac cone phase when incident energy is within the nonlinear band gap.
- The length of the superconductor and pseudospin-valley coupling influence the overall conductance.
Conclusions:
- Kekulé-Y patterned graphene nSp junctions are promising for realizing efficient crossed Andreev reflection.
- The observed phenomenon offers potential for developing novel superconducting electronic devices.
- Understanding the interplay of material properties and quantum effects is key for future advancements.
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