Phase-driven collapse of the Cooper condensate in a nanosized superconductor
| Autor: | Carles Altimiras, Pauli Virtanen, Sophie D'Ambrosio, Francesco Giazotto, Alberto Ronzani |
|---|---|
| Přispěvatelé: | Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), Aalto University, NEST, Instituto Nanoscienze, CNR and Scuola Normale Superiore |
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
[PHYS]Physics [physics]
Superconductivity Physics Condensed matter physics Condensed Matter - Superconductivity Detector FOS: Physical sciences Collapse (topology) 02 engineering and technology Magnetic response 021001 nanoscience & nanotechnology 01 natural sciences Magnetic flux Superconductivity (cond-mat.supr-con) [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con] Core (optical fiber) Phase (matter) Condensed Matter::Superconductivity 0103 physical sciences Phase gradient [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat] 010306 general physics 0210 nano-technology [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall] |
| Zdroj: | Physical Review B 96 (2017). doi:10.1103/PhysRevB.96.214517 info:cnr-pdr/source/autori:Ronzani A.; D'Ambrosio S.; Virtanen P.; Giazotto F.; Altimiras C./titolo:Phase-driven collapse of the Cooper condensate in a nanosized superconductor/doi:10.1103%2FPhysRevB.96.214517/rivista:Physical Review B/anno:2017/pagina_da:/pagina_a:/intervallo_pagine:/volume:96 Physical Review B: Condensed Matter and Materials Physics (1998-2015) Physical Review B: Condensed Matter and Materials Physics (1998-2015), American Physical Society, 2017, 96 (21), ⟨10.1103/PhysRevB.96.214517⟩ Ronzani, A, D'Ambrosio, S, Virtanen, P, Giazotto, F & Altimiras, C 2017, ' Phase-driven collapse of the Cooper condensate in a nanosized superconductor ', Physical Review B, vol. 96, no. 21, 214517 . https://doi.org/10.1103/PhysRevB.96.214517 |
| ISSN: | 1098-0121 1550-235X |
| DOI: | 10.1103/PhysRevB.96.214517 |
| Popis: | Superconductivity can be understood in terms of a phase transition from an uncorrelated electron gas to a condensate of Cooper pairs in which the relative phases of the constituent electrons are coherent over macroscopic length scales. The degree of correlation is quantified by a complex-valued order parameter, whose amplitude is proportional to the strength of the pairing potential in the condensate. Supercurrent-carrying states are associated with non-zero values of the spatial gradient of the phase. The pairing potential and several physical observables of the Cooper condensate can be manipulated by means of temperature, current bias, dishomogeneities in the chemical composition or application of a magnetic field. Here we show evidence of complete suppression of the energy gap in the local density of quasiparticle states (DOS) of a superconducting nanowire upon establishing a phase difference equal to pi over a length scale comparable to the superconducting coherence length. These observations are consistent with a complete collapse of the pairing potential in the center of the wire, in accordance with theoretical modeling based on the quasiclassical theory of superconductivity in diffusive systems. Our spectroscopic data, fully exploring the phase-biased states of the condensate, highlight the profound effect that extreme phase gradients exert on the amplitude of the pairing potential. Moreover, the sharp magnetic response observed near the onset of the superconducting gap collapse regime can be exploited to realize ultra-low noise magnetic flux detectors. Comment: 7 pages, 5 color figures plus supporting info |
| Databáze: | OpenAIRE |
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