Andreev reflection versus Coulomb blockade in hybrid semiconductor nanowire devices

Abstract

Semiconductor nanowires provide promising low-dimensional systems for the study of quantum transport phenomena in combination with superconductivity. Here we investigate the competition between the Coulomb blockade effect, Andreev reflection, and quantum interference, in InAs and InP nanowires connected to aluminum-based superconducting electrodes. We compare three limiting cases depending on the tunnel coupling strength and the characteristic Coulomb interaction energy. For weak coupling and large charging energy, negative differential conductance is observed as a direct consequence of the BCS density of states in the leads. For intermediate coupling and charging energy smaller than the superconducting gap, the current-voltage characteristic is dominated by Andreev reflection and Coulomb blockade produces an effect only near zero bias. For almost ideal contact transparencies and negligible charging energy, we observe universal conductance fluctuations whose amplitude is enhanced due to Andreev reflection at the contacts.

13 pages, 5 figures

References in corpus (7)

• Tunable Supercurrent Through Semiconductor Nanowires
• Supercurrent reversal in quantum dots
• Single-electron tunneling in InP nanowires
• Kondo-Enhanced Andreev Tunneling in InAs Nanowire Quantum Dots
• Lateral electron tunneling through single self-assembled InAs quantum dots coupled to superconducting nanogap electrodes
• Tunneling Density of States, Pair Correlation, and Josephson Current in Spin-Incoherent Luttinger Liquid-Superconductor Hybrid Systems
• Supergap anomalies in cotunneling between N-S and between S-S leads via a small quantum dot

Cited by in corpus (8)

• Multi-mode Fabry-Pérot conductance oscillations in suspended stacking-faults-free InAs nanowires
• Superconductivity-enhanced bias spectroscopy in carbon nanotube quantum dots
• Spectroscopy of the superconducting proximity effect in nanowires using integrated quantum dots
• Quantum dot spectroscopy of proximity-induced superconductivity in a two-dimensional electron gas
• Kondo effect and spin-active scattering in ferromagnet-superconductor junctions
• Charge dynamics in quantum-circuit refrigeration: thermalization and microwave gain
• A particle conserving approach to AC-DC driven interacting quantum dots with superconducting leads
• Vortex detection and quantum transport in mesoscopic graphene Josephson junction arrays