Superconductor-nanowire devices from tunneling to the multichannel regime: Zero-bias oscillations and magnetoconductance crossover

TY - JOUR

T1 - Superconductor-nanowire devices from tunneling to the multichannel regime

T2 - Zero-bias oscillations and magnetoconductance crossover

AU - Churchill, H.O.H.

AU - Fatemi, V.

AU - Grove-Rasmussen, Kasper

AU - Deng, M.T.

AU - Caroff, P.

AU - Xu, H.Q.

AU - Marcus, Charles M.

PY - 2013/6/6

Y1 - 2013/6/6

N2 - We present transport measurements in superconductor-nanowire devices with a gated constriction forming a quantum point contact. Zero-bias features in tunneling spectroscopy appear at finite magnetic fields and oscillate in amplitude and split away from zero bias as a function of magnetic field and gate voltage. A crossover in magnetoconductance is observed: Magnetic fields above ∼0.5 T enhance conductance in the low-conductance (tunneling) regime but suppress conductance in the high-conductance (multichannel) regime. We consider these results in the context of Majorana zero modes as well as alternatives, including the Kondo effect and analogs of 0.7 structure in a disordered nanowire.

AB - We present transport measurements in superconductor-nanowire devices with a gated constriction forming a quantum point contact. Zero-bias features in tunneling spectroscopy appear at finite magnetic fields and oscillate in amplitude and split away from zero bias as a function of magnetic field and gate voltage. A crossover in magnetoconductance is observed: Magnetic fields above ∼0.5 T enhance conductance in the low-conductance (tunneling) regime but suppress conductance in the high-conductance (multichannel) regime. We consider these results in the context of Majorana zero modes as well as alternatives, including the Kondo effect and analogs of 0.7 structure in a disordered nanowire.

U2 - 10.1103/PhysRevB.87.241401

DO - 10.1103/PhysRevB.87.241401

M3 - Journal article

SN - 2469-9950

VL - 87

JO - Physical Review B

JF - Physical Review B

IS - 24

M1 - 241401

ER -