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Updated: May 14, 2026
19:56
Introduction to Solid Supported Membrane Based Electrophysiology
Published on: May 11, 2013
Scale-dependent competing interactions: sign reversal of the average persistent current
H Bary-Soroker1, O Entin-Wohlman, Y Imry
1Physics Department, Ben Gurion University, Beer Sheva 84105, Israel.
Physical Review Letters
|February 19, 2013
Summary
The magnetic response of nanoscale superconductors can shift from diamagnetic to paramagnetic. This occurs when the system
Area of Science:
- Condensed matter physics
- Nanoscale science
Background:
- Superconductors exhibit orbital magnetic responses.
- Nanoscale systems present unique quantum phenomena.
Purpose of the Study:
- To investigate the orbital magnetic response in nanoscale superconductors.
- To analyze the influence of interactions on magnetic properties.
Main Methods:
- Modeling a nanoscale system using persistent current in a ring geometry.
- Evaluating the interplay of renormalized Coulomb and Fröhlich interactions.
Main Results:
- The diamagnetic response of large superconductors can invert to paramagnetic.
- This transition is linked to the Thouless energy relative to Debye energy.
Conclusions:
- Interaction effects significantly alter magnetic response in nanoscale superconductors.
- Finite-size effects are critical in determining the magnetic behavior.
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