Robust Majorana conductance peaks for a superconducting lead

Abstract

Experimental evidence for Majorana bound states largely relies on measurements of the tunneling conductance. While the conductance into a Majorana state is in principle quantized to $2e^2/h$, observation of this quantization has been elusive, presumably due to temperature broadening in the normal-metal lead. Here, we propose to use a superconducting lead instead, whose gap strongly suppresses thermal excitations. For a wide range of tunneling strengths and temperatures, a Majorana state is then signaled by symmetric conductance peaks at $eV=\pm \Delta$ with quantized height $G=(4-\pi )2e^2/h$. For a superconducting scanning tunneling microscope tip, Majorana states appear as spatial conductance plateaus while the conductance varies with the local wavefunction for trivial Andreev bound states. We discuss effects of nonresonant (bulk) Andreev reflections and quasiparticle poisoning.

5 pages, 2 figures plus supplementary material, v2: minor refinements, published version

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Cited by in corpus (46)

• High-resolution studies of the Majorana atomic chain platform
• Majorana nanowires for topological quantum computation
• Low-energy theory of transport in Majorana wire junctions
• Majorana Fermions in Magnetic Chains
• Tomography of Majorana Fermions with STM Tips
• Josephson effect in multiterminal topological junctions
• Photon-assisted resonant Andreev reflections: Yu-Shiba-Rusinov and Majorana states
• Probing Robust Majorana Signatures by Crossed Andreev Reflection with a Quantum Dot
• Majorana Bound States in Double Nanowires with Reduced Zeeman Thresholds due to Supercurrents
• Conductance spectroscopy of nontopological-topological superconductor junctions
• Identifying Majorana bound states by tunneling shot-noise tomography
• Edge mode dynamics of quenched topological wires
• Fingerprints of Majorana fermions in current-correlations measurements from a superconducting tunnel microscope
• Dynamics of hybrid junctions of Majorana wires
• Transport in superconductor--normal metal--superconductor tunneling structures: Spinful p-wave and spin-orbit-coupled topological wires
• Transport signatures of Majorana bound states in superconducting hybrid structures
• Josephson effect in junctions of conventional and topological superconductors
• Majorana differential shot noise and its universal thermoelectric crossover
• Josephson current between topological and conventional superconductors
• Experimental review on Majorana zero-modes in hybrid nanowires
• Single-electron charge transfer into putative Majorana and trivial modes in individual vortices
• Tunneling conductance for Majorana fermions in spin-orbit coupled semiconductor-superconductor heterostructures using superconducting leads
• Thermal signature of Majorana fermions in Josephson junction
• $6\pi$ Josephson effect in Majorana box devices
• Conductance quantization in topological Josephson trijunctions
• Nonequilibrium electrical, thermal and spin transport in open quantum systems of topological superconductors, semiconductors and metals
• Tunneling conductance in semiconductor-superconductor hybrid structures
• Interplay between Majorana and Shiba states in a minimal Kitaev chain coupled to a superconductor
• Probing Majorana zero modes by measuring transport through an interacting magnetic impurity
• The influence of the Majorana non-locality on the supercurrent
• Odd-frequency superconductivity induced in topological insulators with and without hexagonal warping
• Transport signatures of topological phases in double nanowires probed by spin-polarized STM
• Symmetry-breaking signatures of multiple Majorana zero modes in one-dimensional spin-triplet superconductors
• Nonequilibrium finite frequency resonances in differential quantum noise driven by Majorana interference
• Detecting Majorana fermions by use of superconductor-quantum Hall liquid junctions
• Josephson current via an isolated Majorana zero mode
• Quantum Phase Transitions in Proximitized Josephson Junctions
• Nested Defects on the Boundary of Topological Superconductors
• Relation between scattering matrix topological invariants and conductance in Floquet Majorana systems
• Detecting Topological Superconductivity via Berry Curvature Effects in Spectral Functions
• Ising quantum criticality in Majorana nanowires
• Characterizing local Majorana properties using Andreev states
• Thermoelectric fluctuations of interfering Majorana bound states
• Non-Abelian Charge Transport in Three-Flavor Gauge Semimetal Model with Braiding Majoranas
• Fluctuation response of a minimal Kitaev chain in nonequilibrium states
• Detecting and Distinguishing Majorana Zero Modes with the Scanning Tunneling Microscope