Interaction between spin and Abrikosov vortices in doped topological insulators

Abstract

In the topological superconductor with the nematic superconductivity in $E_u$ representation, it is possible to have different types of vortices. One is associated with the vorticity in the particle-hole space and corresponds to the Abrikosov vortex. Another type corresponds to the vorticity in the spin space and is called spin vortex. We study the interaction of the Abrikosov vortex with the spin vortices. We derive the free energy of the sample with the Abrikosov and the strain-induced spin vortices using the Ginzburg-Landau approach for the two-component superconducting order parameter. We calculate the critical strain at which the spin vortex is formed. We show that the spin vortex and the Abrikosov vortex attract to each other and, as a result, they have a common core. We show that there are no zero-energy states (Majorana fermions) localized near the common vortex core of the Abrikosov vortex and the spin vortex of any type. Possible experimental realization is discussed.

References in corpus (8)

• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• Odd-parity topological superconductor with nematic order: Application to CuxBi2Se3
• Visualization of Topological Boundary Modes Manifesting Topological Nodal-Point Superconductivity
• Nematic superconductivity in doped Bi2Se3 topological superconductors
• Breaking of Ginzburg-Landau description in the temperature dependence of the anisotropy in the nematic superconductor
• Pauli paramagnetism of triplet Cooper pairs in a nematic superconductor
• Low-energy in-gap states of vortices in superconductor-semiconductor heterostructures
• Strain induced spin vortex and Majorana Kramer's pairs in doped topological insulators with nematic superconductivity