ISSN:
1572-9605
Keywords:
STM
;
electron tunneling
;
organic superconductors
;
pairing symmetry
Source:
Springer Online Journal Archives 1860-2000
Topics:
Electrical Engineering, Measurement and Control Technology
,
Physics
Notes:
Abstract The superconducting phase of organic superconductors κ-(BEDT-TTF)2Cu(NCS)2 and (MDT-TTF)2AuI2 was investigated by the electron tunneling spectroscopy using low temperature STM. The tunneling differential conductance at the lateral surface of κ-(BEDT-TTF)2Cu(NCS)2 varies its shape depending on the tip direction. The in-plane anisotropy of the conductance is well explained by the d-wave symmetry with line nodes along the direction 45° from the c-axis. For (MDT-TTF)2AuI2, the tunneling conductance at T = 1.4 K shows the superconducting energy gap structure clearly. The finite conductance inside the gap edge suggests the gap anisotropy. The tunneling spectrum is explained by the d-wave pairing. The obtained gap Δ0 = 2 meV (2Δ0/kT c = 12) is larger than that of the weak coupling limit. The pseudogap structure is observed near T c .
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1007732201440
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