Charge-neutral nonlocal response in superconductor-InAs nanowire hybrid devices

Abstract

Nonlocal quasiparticle transport in normal-superconductor-normal (NSN) hybrid structures probes sub-gap states in the proximity region and is especially attractive in the context of Majorana research. Conductance measurement provides only partial information about nonlocal response composed from both electron-like and hole-like quasiparticle excitations. In this work, we show how a nonlocal shot noise measurement delivers a missing puzzle piece in NSN InAs nanowire-based devices. We demonstrate that in a trivial superconducting phase quasiparticle response is practically charge-neutral, dominated by the heat transport component with a thermal conductance being on the order of conductance quantum. This is qualitatively explained by numerous Andreev reflections of a diffusing quasiparticle, that makes its charge completely uncertain. Consistently, strong fluctuations and sign reversal are observed in the sub-gap nonlocal conductance, including occasional Andreev rectification signals. Our results prove conductance and noise as complementary measurements to characterize quasiparticle transport in superconducting proximity devices.

accepted in Semiconductor Science and Technology (Letter)

References in corpus (6)

• Signatures of Majorana fermions in hybrid superconductor-semiconductor nanowire devices
• Majorana Fermions and a Topological Phase Transition in Semiconductor-Superconductor Heterostructures
• Evidence of Majorana fermions in an Al - InAs nanowire topological superconductor
• Majorana bound states in a coupled quantum-dot hybrid-nanowire system
• Andreev rectifier: a nonlocal conductance signature of topological phase transitions
• Presence versus absence of end-to-end nonlocal conductance correlations in Majorana nanowires: Majorana bound states versus Andreev bound states

Cited by in corpus (13)

• Electrostatic control of the proximity effect in the bulk of semiconductor-superconductor hybrids
• Can non-local conductance spectra conclusively signal Majorana zero modes? -- Insights from von Neumann entropy
• Nonlocal measurement of quasiparticle charge and energy relaxation in proximitized semiconductor nanowires using quantum dots
• Quantum Hall Bogoliubov Interferometer
• Edge states, Majorana fermions and topological order in superconducting wires with generalized boundary conditions
• Delocalized states in three-terminal superconductor-semiconductor nanowire devices
• Thermal conductance and non-equilibrium superconductivity in a diffusive NSN wire probed by shot noise
• Probing the topological character of superconductors via non-local Hanbury-Brown and Twiss correlations
• Heat-charge separation in a hybrid superconducting quantum Hall setup
• Fate of the superconducting state in floating islands of hybrid nanowire devices
• $\Delta T$-noise in Multiterminal Hybrid Systems
• Efficient Cooper Pair Splitting Without Interactions
• Conductance measurements cannot distinguish crossed Andreev reflection from elastic co-tunneling in normal--superconductor--normal junctions