Quantum Oscillations in Cu${}_x$Bi${}_2$Se${}_3$ in High Magnetic Fields

Abstract

Cu${}_x$Bi${}_2$Se${}_3$ has drawn much attention as the leading candidate to be the first topological superconductor and the realization of coveted Majorana particles in a condensed matter system. However, there has been increasing controversy about the nature of its superconducting phase. This study sheds light on present ambiguity in the normal state electronic state, by providing a complete look at the quantum oscillations in magnetization in Cu${}_x$Bi${}_2$Se${}_3$ at intense high fields up to 31T. Our study focuses on the angular dependence of the quantum oscillation pattern in a low carrier concentration. As magnetic field tilts from along the crystalline c-axis to ab-plane, the change of the oscillation period follows the prediction of the ellipsoidal Fermi surface. As the doping level changes, the 3D Fermi surface is found to transform into quasi-cylindrical at high carrier density. Such a transition is potentially a Lifshitz transition of the electronic state in Cu${}_x$Bi${}_2$Se${}_3$.

6 pages, 6 figures, submitted to Phys. Rev. B

References in corpus (4)

• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• Bulk Fermi surface coexistence with Dirac surface state in Bi${}_2$Se${}_3$: a comparison of photoemission and Shubnikov-de Haas measurements
• Bulk superconducting phase with a full energy gap in the doped topological insulator Cu_xBi_2Se_3
• Local Measurements of the Superconducting Pairing Symmetry in CuxBi2Se3

Cited by in corpus (4)

• Evidence of nodes in the order parameter of the superconducting doped topological insulator Nb${}_x$Bi${}_2$Se${}_3$ via penetration depth measurements
• Direction and symmetry transition of the vector order parameter in topological superconductors Cu${}_x$Bi${}_2$Se${}_3$
• Three-dimensional Fermi surface and small effective masses in Mo8Ga41
• An increase in $T_c$ under hydrostatic pressure in the superconducting doped topological insulator Nb${}_{0.25}$Bi${}_2$Se${}_3$