Superconducting gap and vortex lattice of the heavy-fermion compound CeCu2Si2
Abstract
The order parameter and pairing mechanism for superconductivity in heavy-fermion compounds are still poorly understood. Scanning tunneling microscopy and spectroscopy at ultralow temperatures can yield important information about the superconducting order parameter and the gap structure. Here, we study the first heavy-fermion superconductor, CeCu2Si2. Our data show the superconducting gap which is not fully formed and exhibits features that point to a multigap order parameter. Spatial mapping of the zero-bias conductance in magnetic field reveals the vortex lattice, which allows us to unequivocally link the observed conductance gap to superconductivity in CeCu2Si2. The vortex lattice is found to be predominantly triangular with distortions at fields close to ∼0.7Hc2.
Citation
Enayat , M , Sun , Z , Maldonado , A , Suderow , H , Seiro , S , Geibel , C , Wirth , S , Steglich , F & Wahl , P 2016 , ' Superconducting gap and vortex lattice of the heavy-fermion compound CeCu 2 Si 2 ' , Physical Review. B, Condensed matter and materials physics , vol. 93 , no. 4 , 045123 . https://doi.org/10.1103/PhysRevB.93.045123
Publication
Physical Review. B, Condensed matter and materials physics
Status
Peer reviewed
ISSN
1098-0121Type
Journal article
Rights
© 2016 American Physical Society. This work is made available online in accordance with the publisher’s policies. This is the final published version of the work, which was originally published at https://dx.doi.org/10.1103/PhysRevB.93.045123
Description
ZS acknowledges support from NWO (grant no. 680.50.1119)Collections
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