Point-contact Andreev-reflection spectroscopy in anisotropic superconductors: the importance of directionality (Review Article)

• Veröffentlicht in: Физика низких температур
• Datum: 2013
• ISSN: 0132-6414
• Hauptverfasser: Daghero, D., Tortello, M., Pecchio, P., Stepanov, V.A., Gonnelli, R.S.
• Format: Artikel
• Sprache: Englisch
• Veröffentlicht: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2013
• Schlagworte: К 75-летию со дня рождения И. К. Янсона
• Online Zugang: https://nasplib.isofts.kiev.ua/handle/123456789/118220
• Назва журналу: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Zitieren: Point-contact Andreev-reflection spectroscopy
 in anisotropic superconductors: the importance
 of directionality
 (Review Article) / D. Daghero, M. Tortello, P. Pecchio, V.A. Stepanov, R.S. Gonnelli // Физика низких температур. — 2013. — Т. 39, № 3. — С. 261–275. — Бібліогр.: 52 назв. — англ.

Point-contact Andreev-reflection spectroscopy (PCARS) has demonstrated to be one of the most effective experimental
 tools for the investigation of fundamental properties of superconductors such as the superconducting
 gap and the electron–phonon (or, more generally, electron–boson) coupling. By reviewing relevant examples reported
 in literature and presenting new results, in this paper we show that when the direction of the interface with
 respect to the crystallographic axes can be controlled (as in single crystals and epitaxial films) PCARS can provide
 invaluable information about the anisotropy of the pairing wavefunction or — in the case of multiband superconductors
 — on the number, amplitude and symmetry of the energy gaps. Moreover, the analysis of PCARS
 results within a suitable 3D generalization of the BTK model allows obtaining qualitative information about the
 topology of the Fermi surface.