Spontaneous breakdown of time-reversal symmetry induced by thermal fluctuations
2015 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 91, no 14, 140504Article in journal (Refereed) Published
In systems with broken U(1) symmetry, such as superfluids, superconductors, or magnets, the symmetry restoration is driven by the proliferation of topological defects in the form of vortex loops (unless the phase transition is strongly first order). Here we discuss that the proliferation of topological defects can, by contrast, lead to the breakdown of an additional symmetry. We demonstrate that this effect should take place in s + is superconductors, which are widely discussed in connection with iron-based materials (although the mechanism is much more general). In these systems a vortex excitation can create a "bubble" of fluctuating Z(2) order parameter. The thermal excitation of vortices then leads to the breakdown of Z(2) time-reversal symmetry when the temperature is increased.
Place, publisher, year, edition, pages
2015. Vol. 91, no 14, 140504
IdentifiersURN: urn:nbn:se:kth:diva-166319DOI: 10.1103/PhysRevB.91.140504ISI: 000352984000001OAI: oai:DiVA.org:kth-166319DiVA: diva2:811221
FunderKnut and Alice Wallenberg FoundationSwedish Research Council, 642-2013-7837 325-2009-7664
QC 201505112015-05-112015-05-072015-05-11Bibliographically approved