Parts | Days | Selection | Search | Downloads | Help
TT: Fachverband Tiefe Temperaturen
TT 15: MLT: Quantum Liquids, Bose-Einstein Condensates, Ultra-cold Atoms, ... 1
TT 15.4: Invited Talk
Tuesday, March 23, 2010, 14:45–15:15, H18
Superconductivity vs. Superinsulation in TiN Thin Films — •Christoph Strunk — Universität Regensburg, D-93040 Regensburg, Germany
TiN thin films display a very sharp superconductor-insulator transition both vs. degree of disorder and vs. magnetic field. In the insulating phase an abrupt drop of the already low, thermally activated conductance is observed below certain threshold voltages Vth, which has been interpreted as the transition to a novel ’superinsulating’ state at very low temperatures [1]. Subsequently, similar experiments on InOx have been interpreted in terms of electron heating of an insulator with a strongly temperature-dependent conductance [2]. The experiments on the insulating side of the transition are complemented by a study of the IV-characteristics on the superconducting side, which demonstrates a striking duality between the transport characteristics on both sides of the transition. Our results are discussed in the light of recent experimental and theoretical developments.
[1] V. Vinokur et al., Nature 452, 613 (2008).
[2] M. Ovadia, B. Sacepe and D. Shahar, PRL 102, 176802 (2009).