[Étude de la structure du gap des supraconducteurs à base de fer par la longueur de pénétration magnétique]
Cet article passe en revue des expériences visant à déterminer la structure du gap supraconducteur dans les supraconducteurs à base de fer. Il se focalise sur les informations obtenues par des mesures de la longueur de pénétration magnétique et de sa dépendance en température, mais les propriétés obtenues par dʼautres moyens de mesures sont aussi examinées, en particulier la conductivité thermique. Lʼarticle comprend une description théorique de base sur les types de structures de gap suggérées pour les supraconducteurs à base de fer, ainsi que la théorie générale de la longueur de pénétration dans les supraconducteurs conventionnels et non conventionnels. Lʼeffet de la diffusion des impuretés sur chacune des structures de gap candidates, important pour lʼinterprétation des données, sera également analysé. Les données de longueurs de pénétration des monocristaux des composés suivants sont examinées : SmFeAsO0.8F0.2, FeTe0.5Se0.5, LaFePO, KFe2As2 et BaFe2(As0.67P0.33)2 ; des matériaux tels que BaFe2As2 dopé par K et Co seront aussi discutés.
This article reviews experiments to determine the structure of the superconducting gap in the iron-based superconductors. It focuses on insights provided by measurements of the temperature dependence of magnetic penetration depth but also discusses the information provided by other measurements especially thermal conductivity. The article includes background theory on the types of gap structure suggested for the iron-based superconductors as well as the general theory of penetration depth in conventional and unconventional superconductors. The effect of impurity scattering on each candidate gap structure is important for the interpretation of data and so will also be discussed. Penetration depth data for single crystals of the following compounds is reviewed: SmFeAsO0.8F0.2, FeTe0.5Se0.5, LaFePO, KFe2As2 and BaFe2(As0.67P0.33)2 along with discussion on related materials such as K- and Co-doped BaFe2As2.
Mot clés : Supraconducteurs à base de fer, Supraconducteurs fer-pnictide, Structure de gap, Longeur de pénétration magnétique
@article{CRPHYS_2011__12_5-6_502_0,
author = {Antony Carrington},
title = {Studies of the gap structure of iron-based superconductors using magnetic penetration depth},
journal = {Comptes Rendus. Physique},
pages = {502--514},
publisher = {Elsevier},
volume = {12},
number = {5-6},
year = {2011},
doi = {10.1016/j.crhy.2011.03.001},
language = {en},
}
Antony Carrington. Studies of the gap structure of iron-based superconductors using magnetic penetration depth. Comptes Rendus. Physique, Volume 12 (2011) no. 5-6, pp. 502-514. doi : 10.1016/j.crhy.2011.03.001. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2011.03.001/
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