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Updated: Jun 3, 2026
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Crossover from weak to strong coupling superconductivity in multi-band systems.
Francisco Dinóla Neto1, Mucio A Continentino, Claudine Lacroix
1Instituto de Física, Universidade Federal Fluminense, Campus da Praia Vermelha, Niterói, RJ, 24.210-340, Brazil.
Summary
This study explores superconductivity in two-band models, revealing a superconducting quantum critical point (SQCP). Pressure tuning and inter-band pairing are key factors in this correlated electron system.
Area of Science:
- Condensed matter physics
- Quantum materials science
Background:
- Superconductivity in correlated electron systems is a key research area.
- Two-band models offer a framework to study complex superconducting phenomena.
Purpose of the Study:
- Investigate superconducting ground states in two-band models with varying effective masses.
- Analyze the impact of pressure-tuned hybridization and inter-band pairing on superconductivity.
- Explore the BCS-BEC crossover and the emergence of a superconducting quantum critical point (SQCP).
Main Methods:
- Utilized two-band models with tunable hybridization.
- Introduced s-wave scattering length to study the strong coupling regime.
- Calculated superconducting order parameters and chemical potential at T=0.
- Analyzed the phase diagram as a function of external pressure.
Main Results:
- Demonstrated the occurrence of a superconducting quantum critical point (SQCP) in the two-band model.
- Obtained superconducting order parameters and chemical potential along the BCS-BEC crossover.
- Characterized the phase diagram influenced by pressure and hybridization.
Conclusions:
- The two-band model provides a platform for understanding pressure-tuned superconductivity.
- Results are applicable to real-world systems like Fe pnictides and heavy fermions.
- Identified the SQCP as a significant feature in these correlated systems.
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