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Title: Hard Superconductivity of a Soft Metal in the Quantum Regime

Abstract

Superconductivity is inevitably suppressed in reduced dimensionality. Questions of how thin superconducting wires or films can be before they lose their superconducting properties have important technological ramifications and go to the heart of understanding coherence and robustness of the superconducting state in quantum-confined geometries. Here, we exploit quantum confinement of itinerant electrons in a soft metal, Pb, to stabilize superconductors with lateral dimensions of the order of a few millimetres and vertical dimensions of only a few atomic layers. These extremely thin superconductors show no indication of defect- or fluctuation-driven suppression of superconductivity, and sustain supercurrents of up to 10% of the depairing current density. Their magnetic hardness implies a Bean-like critical state with strong vortex pinning that is attributed to quantum trapping of vortices. This study paints a conceptually appealing, elegant picture of a model nanoscale superconductor with calculable critical-state properties and surprisingly strong phase coherence. It indicates the intriguing possibility of exploiting robust superconductivity at the nanoscale.

Authors:
 [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
OE USDOE - Office of Electric Transmission and Distribution
OSTI Identifier:
978165
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nature Physics; Journal Volume: 2; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CONFINEMENT; CURRENT DENSITY; DIMENSIONS; ELECTRONS; HARDNESS; SUPERCONDUCTING WIRES; SUPERCONDUCTIVITY; SUPERCONDUCTORS; TRAPPING; VORTICES

Citation Formats

Ozer, Mustafa M, Thompson, James R, and Weitering, Harm H. Hard Superconductivity of a Soft Metal in the Quantum Regime. United States: N. p., 2006. Web. doi:10.1038/nphys244.
Ozer, Mustafa M, Thompson, James R, & Weitering, Harm H. Hard Superconductivity of a Soft Metal in the Quantum Regime. United States. doi:10.1038/nphys244.
Ozer, Mustafa M, Thompson, James R, and Weitering, Harm H. Sun . "Hard Superconductivity of a Soft Metal in the Quantum Regime". United States. doi:10.1038/nphys244.
@article{osti_978165,
title = {Hard Superconductivity of a Soft Metal in the Quantum Regime},
author = {Ozer, Mustafa M and Thompson, James R and Weitering, Harm H},
abstractNote = {Superconductivity is inevitably suppressed in reduced dimensionality. Questions of how thin superconducting wires or films can be before they lose their superconducting properties have important technological ramifications and go to the heart of understanding coherence and robustness of the superconducting state in quantum-confined geometries. Here, we exploit quantum confinement of itinerant electrons in a soft metal, Pb, to stabilize superconductors with lateral dimensions of the order of a few millimetres and vertical dimensions of only a few atomic layers. These extremely thin superconductors show no indication of defect- or fluctuation-driven suppression of superconductivity, and sustain supercurrents of up to 10% of the depairing current density. Their magnetic hardness implies a Bean-like critical state with strong vortex pinning that is attributed to quantum trapping of vortices. This study paints a conceptually appealing, elegant picture of a model nanoscale superconductor with calculable critical-state properties and surprisingly strong phase coherence. It indicates the intriguing possibility of exploiting robust superconductivity at the nanoscale.},
doi = {10.1038/nphys244},
journal = {Nature Physics},
number = 3,
volume = 2,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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