Effects of the electrostatic environment on superlattice Majorana nanowires

Abstract

Finding ways of creating, measuring and manipulating Majorana bound states (MBSs) in superconducting-semiconducting nanowires is a highly pursued goal in condensed matter physics. It was recently proposed that a periodic covering of the semiconducting nanowire with superconductor fingers would allow both gating and tuning the system into a topological phase while leaving room for a local detection of the MBS wavefunction. We perform a detailed, self-consistent numerical study of a three-dimensional (3D) model for a finite-length nanowire with a superconductor superlattice including the effect of the surrounding electrostatic environment, and taking into account the surface charge created at the semiconductor surface. We consider different experimental scenarios where the superlattice is on top or at the bottom of the nanowire with respect to a back gate. The analysis of the 3D electrostatic profile, the charge density, the low energy spectrum and the formation of MBSs reveals a rich phenomenology that depends on the nanowire parameters as well as on the superlattice dimensions and the external back gate potential. The 3D environment turns out to be essential to correctly capture and understand the phase diagram of the system and the parameter regions where topological superconductivity is established.

20 pages, 19 figures. Published version. Supplementary Information is available as ancillary file, raw data and calculations can be downloaded from https://zenodo.org/record/3250709#.XSRNnibtZuU

References in corpus (13)

• Non-Abelian Anyons and Topological Quantum Computation
• Signatures of Majorana fermions in hybrid superconductor-semiconductor nanowire devices
• Majorana Fermions and a Topological Phase Transition in Semiconductor-Superconductor Heterostructures
• Observation of Majorana Fermions in Ferromagnetic Atomic Chains on a Superconductor
• Majorana bound states in a coupled quantum-dot hybrid-nanowire system
• Hard gap in epitaxial semiconductor-superconductor nanowires
• Transport spectroscopy of NS nanowire junctions with Majorana fermions
• Search for Majorana fermions in multiband semiconducting nanowires
• Detecting Majoranas in 1D wires by charge sensing
• Electron temperature and tunnel coupling dependence of zero-bias and almost-zero-bias conductance peaks in Majorana nanowires
• Zero-energy pinning from interactions in Majorana nanowires
• Finite-size effects in a nanowire strongly coupled to a thin superconducting shell
• Realizing Topological Superconductivity with Superlattices

Cited by in corpus (15)

• Majorana nanowires for topological quantum computation
• Estimating disorder and its adverse effects in semiconductor Majorana nanowires
• Numerical study of PbTe-Pb hybrid nanowires for engineering Majorana zero modes
• Subband occupation in semiconductor-superconductor nanowires
• Enhanced topological superconductivity in spatially modulated planar Josephson junctions
• Recent progress on Majorana in semiconductor-superconductor heterostructures--Engineering and detection
• Semiconductor-ferromagnet-superconductor planar heterostructures for 1D topological superconductivity
• One-dimensional topological superconductivity based entirely on phase control
• Progress in superconductor-semiconductor topological Josephson junctions
• Fluxoid-induced pairing suppression and near-zero modes in quantum dots coupled to full-shell nanowires
• Spectroscopic Visualization of a Robust Electronic Response of Semiconducting Nanowires to Deposition of Superconducting Islands
• The feedback driven atomic scale Josephson microscope
• Gapfull and gapless $1$D Topological Superconductivity in Spin-Orbit Coupled Bilayer Graphene
• Topological superconducting phase in a non-Hermitian Kitaev chain with staggered pairing imbalance
• Electrostatics in semiconducting devices I : The Pure Electrostatics Self Consistent Approximation