Anomalous Nernst effect in the mixed state of the two-band organic superconductors κ-(BEDT-TTF)2Cu[N(CN)2]Br and κ-(BEDT-TTF)2Cu(NCS)2

✍ Scribed by G.Yu. Logvenov; H. Ito; T. Ishiguro; G. Saito; S. Takasaki; J. Yamada; H. Anzai

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 475 KB
• Volume: 264
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(96)00243-2

✦ Synopsis

The transverse thermomagnetic Nemst effect in the mixed state of the organic superconducting salts of the r-(BEDTq'q'F)2X family, where BEDT-q'TF is bis(ethylenedithio)tetrathiafulvalene and X--Cu[N(CN)2]Br and Cu(NCS)2, has been studied as regards temperature under a magnetic field for different in-plane crystal directions. A large anisotropy of the in-plane Nernst voltage in the conducting plane with a sign change has been observed and is discussed considering the flux motion from the viewpoint of the entropy and Magnus forces. The experimental results can be explained taking into account the anisotropic two-band nature of the conducting system in these compounds and assuming a predominant role of the electron-like band in the superconducting pairing. The peculiarities of the inter-plane Nernst effect in the K-(BEDT-TFF)2Cu(NCS)2 salt confirms the proposed interpretation. In this case the Nernst voltage is related to the thermal diffusion of the Josephson vortices.