Extended Data Fig. 1: Three terminal measurement setups, extended data of the tunnel barrier gate dependence of the ZBCP and the effect of the contact resistance.
From: Non-Majorana states yield nearly quantized conductance in proximatized nanowires
a, Schematics of the device and measurement setups. Red arrows indicate the direction of dc current flow for positive bias. The source-drain voltage is applied through the superconducting contact, current and differential conductance are measured simultaneously at two normal contacts. The two wider tunnel gates are connected together as T3. b, Simplified measurement circuit diagram representing all elements of the circuit as resistors. Rfilters is the resistance of RC filters and Rim is the input impedance of the current amplifier. Dashed box indicates on chip elements. The nanowire segment in contact with NbTiN is a multi-terminal conductor which can be fully characterized by a resistance tensor, R\({\,}_{{\rm{Nanowire}}}\), which is the resistance of the nanowire segment between the normal contacts. Semiconductor-normal metal contact resistances are indicated by R\({\,}_{{\rm{L}}^{\prime} }\) and R\({\,}_{{\rm{R}}^{\prime} }\). The exact values of contact resistances are unknown, but they can be estimated from saturation current at positive gate voltages. c and d, Differential conductance GL and GR as functions of TL voltage and source-drain voltage from the same dataset as Fig. 2(d). The gate settings are S-gate = -0.17 V and TR = -0.105 V. e, Zero bias linecuts from panel c with different R\(^{\prime}\) subtracted. When 0, 1 kΩ, 2 kΩ, 3 kΩ, 4 kΩ, 5 kΩ are subtracted (from bottom to top), the conductance plateau increases from 0.8*2e2/h to 1.1*2e2/h. f, Bias linecuts at TL= -0.05 V (yellow dashed line) from panel c and panel d show the shape of the ZBCP on the left side and absence of clear ZBCP on the right side.
