Visualizing pairing symmetry in nematic superconductors using spin-polarized spectroscopy of magnetic impurities

Abstract

We study the spin-polarized spectral properties of Yu-Shiba-Rusinov resonance states induced by magnetic impurities in 2-and 3-dimensional nematic superconductors: few layer Bi2Te3 grown on FeTe0.55Se0.45 (2-dimensional) and CuxBi2Se3 (3-dimensional). We focus on the relationship between pairing symmetry and the topograph of spin-polarized spectroscopy. We calculate the spin-polarized local density of states (SP LDOS) and the corresponding Fourier transformation using the T -matrix method for both the 2-and 3-dimensional materials. Various situations with different impurity orientations and different SP LDOSs have been investigated. We find that, like the quasiparticle interference spectrum, the SP LDOS can be applied to distinguish other pairings which preserve the threefold rotation symmetry of D3 point group and nematic pairings in these materials.

Kondo screening cloud in a superconductor with mixed s-wave and p-wave pairing states

“…The interest in magnetic doping in superconductors persists because it can provide information to understanding the properties of superconducting states. The properties of YSR states is one of the major methods to characterize the pairing symmetry of the superconducting states, and has been widely studied in the high-temperature cuprate superconductors, [7][8][9][10] iron-based superconductors, [11][12][13] chiral p-wave superconductors, [14,15] topological superconductors, [16,17] nematic superconductors, [18] etc. More recently, the pairing symmetry dependent YSR states are studied in the superconducting phase of twisted bilayer graphene.…”

Influence of Dopant Uniformity on Electron Transport in CuxBi2Se3 Films

“…M x Bi 2 Se 3 (M = Cu, Sr, Nb) is found to be a good candidate for a nematic topological superconductor (TSC) with 3-fold rotational symmetry breaking and has attracted a great deal of recent attention. ,− A basic issue that has been largely ignored in studying doped Bi 2 Se 3 is the uniformity of dopants despite the fact that is evidence for the nonuniformity of the Cu or segregations of Cu clusters, even Cu-rich precipitates. − ,, Thus, the influence of the intercalated Cu’s uniformity on the topological surface state in Cu x Bi 2 Se 3 is something that needs to be understood. It is known that the weak antilocalization (WAL), which appears as a diplike positive magnetoresistance (MR) in the low magnetic field region, − could be a characteristic feature in transport experiments demonstrating the presence of the Dirac fermions in disordered TIs .…”