Stability of topological defects in chiral superconductors: London theory

Abstract

This paper examines thermodynamic stability of chiral domain walls and vortices - topological defects which can exist in chiral superconductors. Using London theory it is demonstrated that at sufficiently small applied and chiral fields the existence of domain walls and vortices in the sample is not favored and the sample's configuration is a single domain. The particular chirality of the single-domain configuration is neither favored nor disfavored by the applied field. Increasing the field leads to an entry of a domain wall loop or a vortex into the sample. Formation of a straight domain wall is never preferred in equilibrium. Values of the entry (critical) fields for both types of defects, as well as the equilibrium size of the domain wall loop, are calculated. We also consider a mesoscopic chiral sample and calculate its zero-field magnetization, susceptibility and a change in the magnetic moment due to a vortex or a domain wall entry. We show that in a case of a soft domain wall whose energetics is dominated by the chiral current (and not by the surface tension) its behavior in mesoscopic samples is substantially different from that in the bulk case and can be used for a controllable transfer of edge excitations. The applicability of these results to Sr2RuO4 - a tentative chiral superconductor - is discussed.

Published version with minor grammatical changes

References in corpus (5)

• High Resolution Polar Kerr Effect Measurements of Sr2RuO4: Evidence for Broken Time Reversal Symmetry in the Superconducting State
• Observation of half-height magnetization steps in Sr2RuO4
• Density waves and Cooper pairing on the honeycomb lattice
• Is Sr2RuO4 a Chiral P-Wave Superconductor?
• Magnetic fields above the surface of a superconductor with internal magnetism

Cited by in corpus (8)

• Skyrmionic state and stable half-quantum vortices in chiral p-wave superconductors
• Vortex coalescence and type-1.5 superconductivity in Sr2RuO4
• Majorana Fermion Rides on a Magnetic Domain Wall
• Optical Manipulation of Domains in Chiral Topological Superconductors
• Annihilation dynamics of stringlike topological defects in a nematic lyotropic liquid crystal
• Nucleation of domain walls by $Z_2$ symmetry breaking transition in $p_x+i{p}_y$ superconductors
• Mesoscopic p-wave superconductor near the phase transition temperature
• DC-current induced domain wall in a chiral $p$-wave superconductor