Superconductivity Near Transition to Insulating State in MoC Ultrathin Films Studied by Subkelvin STM

• Authors: P. Szabó , P. Neilinger , M. Trgala , M. Grajcar , P. Samuely
• Languages of publication: EN

Abstracts

EN

We study the homogeneously disordered MoC thin films with thicknesses of 10 and 5 nm and the superconducting transition temperatures near 6 and 4 K, significantly decreased as compared to the bulk T_{c}=8.32 K due to a disorder. The scanning tunnelling spectroscopy reveals in the thicker sample a BCS superconducting energy gap Δ with a broadening parameter Γ equal to about 10 per cent of Δ. Remarkably, Γ increases with temperature. The thinner, more disordered sample shows a gapped superconducting density of states but without any coherence peaks at the gap edge, which could not be approximated by the BCS DOS. Moreover, the reduced DOS around the Fermi level persists above the resistive transition temperature reminding the pseudo-gap known from high-T_{c} cuprates.

Keywords

EN

74.50.+r; 74.78.-w; 74.81.-g

Discipline

• 74.81.-g: Inhomogeneous superconductors and superconducting systems, including electronic inhomogeneities
• 74.78.-w: Superconducting films and low-dimensional structures
• 74.50.+r: Tunneling phenomena; Josephson effects(for SQUIDs, see 85.25.Dq; for Josephson devices, see 85.25.Cp; for Josephson junction arrays, see 74.81.Fa)

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2014
• Volume: 126
• Issue: 1
• Pages: 368-369

Dates

published

2014-07

Contributors

author

P. Szabó

• Centre of Low Temperature Physics @ Institute of Experimental Physics, Slovak Academy of Sciences, Park Angelinum 9, 040 01 Košice, Slovakia

author

P. Neilinger

• Comenius University, Department of Solid State Physics, 84248 Bratislava, Slovakia

author

M. Trgala

• Comenius University, Department of Solid State Physics, 84248 Bratislava, Slovakia

author

M. Grajcar

• Comenius University, Department of Solid State Physics, 84248 Bratislava, Slovakia

author

P. Samuely

• Centre of Low Temperature Physics @ Institute of Experimental Physics, Slovak Academy of Sciences, Park Angelinum 9, 040 01 Košice, Slovakia

References

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Identifiers

DOI

10.12693/APhysPolA.126.368