Physics
Critical field and Shubnikov-de Haas oscillations of κ-(BEDT-TTF)2Cu(NCS)2 under pressure
Document Type
Article
Abstract
We have used a novel experimental method to study the crossover of an anisotropic superconductor from a possible Pauli limited superconducting state to a vortex limited superconducting state by applying pressure. The new apparatus combined a tuned tank circuit with a nonmetallic diamond anvil cell to measure the change in critical field with angle in κ-(BEDT-TTF)2Cu(NCS)2 at pressures up to 1.75 kbar and at temperatures down to 70 mK. The critical fields (in the perpendicular or parallel orientation to the conducting planes) have been found to decrease by more than 90% within less than 2 kbar of pressure. In the parallel orientation, at 1.75 kbar, we have seen a clear change from the ambient pressure behavior of the critical field with temperature at low temperatures. Up to P = 1.75 kbar, the Hc2(θ) phase diagram is in good agreement with the theoretical prediction for weakly coupled layered superconductors. We have also succeeded in measuring oscillations in the resistivity of the normal state at higher magnetic field which could be used to find the effective quasi-particle mass. The α-orbit Shubnikov-de Haas frequency was found to increase at a rate of 44T/kbar. Our experiment opens the possibility for further investigations of the effective mass with pressure, especially because the setup is suitable for pulsed fields as well. © 2005 Springer Science+Business Media, Inc.
Publication Title
Journal of Low Temperature Physics
Publication Date
3-2005
Volume
138
Issue
5-6
First Page
1025
Last Page
1037
ISSN
0022-2291
DOI
10.1007/s10909-004-2898-8
Keywords
FFLO state, Pauli limited, Shubnikov-de Haas oscillations
Repository Citation
Martin, C.; Agosta, C. C.; Tozer, S. W.; Radovan, H. A.; Kinoshota, T.; and Tokumoto, M., "Critical field and Shubnikov-de Haas oscillations of κ-(BEDT-TTF)2Cu(NCS)2 under pressure" (2005). Physics. 33.
https://commons.clarku.edu/faculty_physics/33
Cross Post Location
Student Publications
