Bulletin of the American Physical Society
APS March Meeting 2012
Volume 57, Number 1
Monday–Friday, February 27–March 2 2012; Boston, Massachusetts
Session Q10: Invited Session: Rare Fluctuation Effects in Strongly Disordered Systems
11:15 AM–2:15 PM,
Wednesday, February 29, 2012
Sponsoring Units: DCMP DCOMP
Chair: Susan Coppersmith, University of Wisconsin
Abstract ID: BAPS.2012.MAR.Q10.4
Abstract: Q10.00004 : Gaps and Pseudogaps across the inhomogeneous superconductor to paired insulator transition*
1:03 PM–1:39 PM
Preview Abstract Abstract
(Ohio State University)
The mechanism for the disorder-tuned superconductor to insulator transition (SIT) in thin films and the nature of the resulting insulator are still debated, despite decades of research. We use quantum Monte Carlo simulations  that treat, on an equal footing, inhomogeneous amplitude variations and phase fluctuations, and go beyond our earlier Bogoliubov-deGennes analysis . We gain new microscopic insights into the SIT, compare our theory with experiments  and make testable predictions for local spectroscopic probes. The energy gap in the single-particle density of states survives across the transition, but coherence peaks exist only in the superconducting state. A characteristic pseudogap persists above the critical disorder and critical temperature, in contrast to conventional theories. Surprisingly, the insulator has signatures of pairing with a two-particle gap scale that vanishes at the superconductor--insulator transition, despite a robust single-particle gap. The impact of rare regions on the gaps will also be discussed. In collaboration with K. Bouadim, Y.L.Loh and N. Trivedi. \\[4pt]  K. Bouadim, Y.L.Loh, M. Randeria and N. Trivedi, Nature Phys. 7, 884 (2011). \\[0pt]  A. Ghosal, M. Randeria, and N. Trivedi, Phys. Rev. B 65, 014501 (2001). \\[0pt]  B. Sacepe et al., Nature Comm. 1, 140 (2010); Nature Phys. 7, 239 (2011); M. Mondal et al., Phys. Rev. Lett. 106, 047001 (2011).
*Supported by NSF DMR-0907275 (K.B.), DOE BES DE-FG02-07ER46423 (N.T., Y.L.L.), and NSF DMR-1006532 (M.R.).
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2012.MAR.Q10.4
The American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics.
1 Physics Ellipse, College Park, MD 20740-3844
Editorial Office 1 Research Road, Ridge, NY 11961-2701 (631) 591-4000
Office of Public Affairs 529 14th St NW, Suite 1050, Washington, D.C. 20045-2001 (202) 662-8700