Creuzet, FrancoisBourbonnais, ClaudeCreuzet, GerardJerome, DenisSchweitzer, DieterKeller, Heimo J.2011-07-212016-03-312011-07-212016-03-311986352749725http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-64553http://elib.uni-stuttgart.de/handle/11682/7622http://dx.doi.org/10.18419/opus-7605We have investigated the nature and the stability of the high-Tc(∼8 K) and low-Tc (∼1.5 K)superconducting phases (respectively called β-H and β-L) of the organic conductor β-(BEDT-TTF)2I3. First, by resistivity measurements and following a well-defined temperature-pressure cycling process, we show that the β-H phase is stabilized at ambient pressure and low temperature, exhibiting a very sharp and complete superconducting transition at 8.1 K and 1 bar. Secondly, an AC-susceptibility study reveals that this state is stable and exhibits bulk superconductivity at high Tc and ambient P as long as the sample is not warmed above 125 K. Finally, we present NMR results on the 1H spin-lattice relaxation rate behaviour in both the β-H phase and the β-L phase.eninfo:eu-repo/semantics/openAccessOrganischer Supraleiter , Tetrathiafulvalen530Two superconducting phases in the organic conductor: β-(BEDT-TTF)2I3article