Field-angle-dependent low-energy excitations around a vortex in the superconducting topological insulator CuxBi2Se3

Abstract

We study the quasiparticle excitations around a single vortex in the superconducting topological insulator Cu${}_x$Bi${}_2$Se${}_3$, focusing on a superconducting state with point nodes. Inspired by the recent Knight shift measurements, we propose two ways to detect the positions of point nodes, using an explicit formula of the density of states with Kramer-Pesch approximation in the quasiclassical treatment. The zero-energy local density of states around a vortex parallel to the $c$-axis has a twofold shape and splits along the nodal direction with increasing energy; these behaviors can be detected by the scanning tunneling microscopy. An angular dependence of the density of states with a rotating magnetic field on the $a$-$b$ plane has deep minima when the magnetic field is parallel to the directions of point nodes, which can be detected by angular-resolved heat capacity and thermal conductivity measurements. All the theoretical predictions are detectable via standard experimental techniques in magnetic fields.

arXiv comment5 pages, 2 figures, to be published in J. Phys. Soc. Jpn

References in corpus (31)

• Topological Insulators
• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• $Z_2$ Topological Order and the Quantum Spin Hall Effect
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Topological Insulators in Three Dimensions
• Topological Insulators with Inversion Symmetry
• Topological invariants of time-reversal-invariant band structures
• Superconductivity in CuxBi2Se3 and its implications for pairing in the undoped topological insulator
• Odd-Parity Topological Superconductors: Theory and Application to Cu${}_x$Bi${}_2$Se${}_3$
• Topological Superconductivity in CuxBi2Se3
• Observation of topological order in a Superconducting doped topological insulator (based on the Bi2Se3 class)
• Bulk superconducting phase with a full energy gap in the doped topological insulator Cu_xBi_2Se_3
• Direct Evidence for the Dirac-Cone Topological Surface States in Ternary Chalcogenide TlBiSe2
• Local Measurements of the Superconducting Pairing Symmetry in CuxBi2Se3
• Observation of Single Dirac Cone Topological Surface State in Compounds TlBiTe2 and TlBiSe2 from a New Topological Insulator Family
• Nodal Structure of Unconventional Superconductors Probed by the Angle Resolved Thermal Transport Measurements
• Direct mapping of the spin-filtered surface bands of a three-dimensional quantum spin Hall insulator
• Tunneling Conductance and Surface States Transition in Superconducting Topological Insulators
• Unconventional superconductivity in CuxBi2Se3
• Surface spectral function in the superconducting state of a topological insulator
• Star-shaped Local Density of States around Vortices in a Type II Superconductor
• Effects of gap anisotropy upon the electronic structure around a superconducting vortex
• Bulk electronic state of superconducting topological insulator
• Phase-Sensitive Impurity Effects in Vortex Core of Moderately Clean Chiral Superconductors
• Rotational Isotropy Breaking as Proof for Spin-polarized Cooper Pairs in the Topological Superconductor CuxBi2Se3
• Analytical Formulation of the Local Density of States around a Vortex Core in Unconventional Superconductors
• Superconducting gap function in the organic superconductor (TMTSF)2ClO4 with anion ordering; First-principles calculations and quasiclassical analysis for angle-resolved heat capacity
• Positions of Point-Nodes in Borocarbide Superconductor YNi2B2C
• Kramer-Pesch approximation for analyzing field-angle-resolved measurements made in unconventional superconductors: A calculation of the zero-energy density of states
• Quasiclassical Treatment and Odd-parity/Triplet Correspondence in Topological Superconductors
• Analytical Result on Electronic States around a Vortex Core in a Noncentrosymmetric Superconductor

Cited by in corpus (11)

• Thermodynamic evidence for nematic superconductivity in Cu${}_x$Bi${}_2$Se${}_3$
• Odd-parity topological superconductor with nematic order: Application to CuxBi2Se3
• Superconductivity in doped Dirac semimetals
• Superconducting doped topological materials
• Surface electronic state of superconducting topological crystalline insulator
• Non-fragile superconductivity with nodes in the superconducting topological insulator CuxBi2Se3: Zeeman orbital field and non-magnetic impurities
• Visualizing the $d$-vector in a nematic triplet superconductor
• Nuclear magnetic relaxation rates of unconventional superconductivity in doped topological insulators
• Inverse coherence effects in nuclear magnetic relaxation rates as a sign of topological superconductivity
• Quasiparticle Bound States around Fractional Vortices in s-wave Superconductor
• Quantized bound states around a vortex in anisotropic superconductors