Topological protection, disorder, and interactions: Survival at the surface of three-dimensional topological superconductors

dc.citation.firstpage155140
dc.citation.journalTitlePhysical Review B
dc.citation.volumeNumber89
dc.contributor.authorFoster, Matthew S.
dc.contributor.authorXie, Hong-Yi
dc.contributor.authorChou, Yang-Zhi
dc.date.accessioned2014-08-01T19:09:24Z
dc.date.available2014-08-01T19:09:24Z
dc.date.issued2014
dc.description.abstractWe consider the interplay of disorder and interactions upon the gapless surface states of 3D topological superconductors. The combination of topology and superconducting order inverts the action of time-reversal symmetry, so that extrinsic time-reversal invariant surface perturbations appear only as “pseudomagnetic” fields (Abelian and non-Abelian vector potentials, which couple to spin and valley currents). The main effect of disorder is to induce multifractal scaling in surface state wave functions. These critically delocalized, yet strongly inhomogeneous states renormalize interaction matrix elements relative to the clean system. We compute the enhancement or suppression of interaction scaling dimensions due to the disorder exactly, using conformal field theory. We determine the conditions under which interactions remain irrelevant in the presence of disorder for symmetry classes AIII and DIII. In the limit of large topological winding numbers (many surface valleys), we show that the effective field theory takes the form of a Finkel’stein nonlinear sigma model, augmented by the Wess-Zumino-Novikov-Witten term. The sigma model incorporates interaction effects to all orders and provides a framework for a controlled perturbative expansion; the inverse spin or thermal conductance is the small parameter. For class DIII, we show that interactions are always irrelevant, while in class AIII, there is a finite window of stability, controlled by the disorder. Outside of this window, we identify new interaction-stabilized fixed points.
dc.identifier.citationFoster, Matthew S., Xie, Hong-Yi and Chou, Yang-Zhi. "Topological protection, disorder, and interactions: Survival at the surface of three-dimensional topological superconductors." <i>Physical Review B,</i> 89, (2014) American Physical Society: 155140. http://dx.doi.org/10.1103/PhysRevB.89.155140.
dc.identifier.doihttp://dx.doi.org/10.1103/PhysRevB.89.155140
dc.identifier.urihttps://hdl.handle.net/1911/76320
dc.language.isoeng
dc.publisherAmerican Physical Society
dc.rightsArticle is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
dc.titleTopological protection, disorder, and interactions: Survival at the surface of three-dimensional topological superconductors
dc.typeJournal article
dc.type.dcmiText
dc.type.publicationpublisher version
Files
Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
PhysRevB.89.155140.pdf
Size:
1.45 MB
Format:
Adobe Portable Document Format
Description: