Evidence of Andreev bound states as a hallmark of the FFLO phase in κ-(BEDT-TTF)2Cu(NCS)2.

Saved in:

Bibliographic Details
Title:	Evidence of Andreev bound states as a hallmark of the FFLO phase in κ-(BEDT-TTF)2Cu(NCS)2.
Authors:	Mayaffre, H.¹, Krämer, S.¹, Horvatić, M.¹, Berthier, C.¹, Miyagawa, K.², Kanoda, K.², Mitrović, V. F.³
Source:	Nature Physics. Dec2014, Vol. 10 Issue 12, p928-932. 5p. 5 Graphs.
Subjects:	Andreev reflection, Superconductivity, Fermions, Quantum chromodynamics, Nuclear magnetic resonance, Electron spin echoes, Mathematical models
Abstract:	Superconductivity is a quantum phenomenon arising, in its simplest form, from the pairing of fermions with opposite spin into a state with zero net momentum. Whether superconductivity can occur in fermionic systems with an unequal number of two species distinguished by spin or flavour presents an important open question in condensed-matter physics or quantum chromodynamics. In condensed matter the imbalance between spin-up and spin-down electrons that form the Cooper pairs is induced by the magnetic field. Such an imbalanced system can lead to exotic superconductivity in which pairs acquire finite momentum. This momentum leads to a spatially inhomogeneous state consisting of periodically alternating 'normal' and 'superconducting' regions. Here, we establish that the hallmark of this state is the appearance of spatially localized and spin-polarized quasiparticles forming the so-called Andreev bound states (ABS). These are detected through our nuclear magnetic resonance (NMR) measurements. [ABSTRACT FROM AUTHOR]
	Copyright of Nature Physics is the property of Springer Nature and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database:	Engineering Source

Description
Abstract:	Superconductivity is a quantum phenomenon arising, in its simplest form, from the pairing of fermions with opposite spin into a state with zero net momentum. Whether superconductivity can occur in fermionic systems with an unequal number of two species distinguished by spin or flavour presents an important open question in condensed-matter physics or quantum chromodynamics. In condensed matter the imbalance between spin-up and spin-down electrons that form the Cooper pairs is induced by the magnetic field. Such an imbalanced system can lead to exotic superconductivity in which pairs acquire finite momentum. This momentum leads to a spatially inhomogeneous state consisting of periodically alternating 'normal' and 'superconducting' regions. Here, we establish that the hallmark of this state is the appearance of spatially localized and spin-polarized quasiparticles forming the so-called Andreev bound states (ABS). These are detected through our nuclear magnetic resonance (NMR) measurements. [ABSTRACT FROM AUTHOR]
ISSN:	17452473
DOI:	10.1038/nphys3121