Zero-bias conductance quantization in a normal / superconducting junction of nano wire

Zero-bias conductance quantization in a normal / superconducting junction of nano wire

We discuss a strong relationship between Majorana fermions and odd-frequency Cooper pairs which appear at a disordered normal nano wire attached to a topologically nontrivial superconducting one. The zero-bias differential conductance in a normal / superconducting nano wire junctions is quantized at 2e/h irrespective of degree of disorder, length of disordered segment, and random realization of...

Conductance quantization and zero bias peak in a gated quantum wire

Conductance measurements are reported for an 0.4 mm wide GaAs/AlGaAs quantum wire with 7 cross-channel gates. The device exhibited integral conductance steps, magnetoconductance plateaus in agreement with the multiprobe formula and a conductance feature at 0.65(2e/h). Differential conductance measurements down to 50mK revealed a zero bias conductance peak that vanished with an in-plane field of...

Giant Zero-Bias Conductance and Multiple Andreev Reflections in Carbon Nanotubes with Superconducting Contacts

Superconducting metal leads strongly modify the electronic conductance through carbon nanotubes. Depending on the nanotube transparency, which is controlled by the gate voltage, we observe a strong enhancement of the zero-bias conductance (way above the ballistic limit of 4e/h) or formation of a tunneling gap. Subgap structures corresponding to the Multiple Andreev Reflections are also found. A...

Thermal dependence of the zero-bias conductance through a nanostructure

We show that the conductance of a quantum wire side-coupled to a quantum dot, with a gate potential favoring the formation of a dot magnetic moment, is a universal function of the temperature. Universality prevails even if the currents through the dot and the wire interfere. We apply this result to the experimental data of Sato et al. [Phys. Rev. Lett. 95, 066801 (2005)]. Nanodevices owe much o...

[Article] Appearance of the universal value e2/h of the zero-bias conductance in a Weyl semimetal-superconductor junction