Joint measurement of current-phase relations and transport properties of hybrid junctions using a three junctions SQUID

Abstract

We propose a scheme to measure both the current-phase relation and differential conductance $dI/dV$ of a superconducting junction, in the normal and the superconducting states. This is done using a dc Superconducting Quantum Interference Device (dc SQUID) with two Josephson junctions in parallel with the device under investigation and three contacts. As a demonstration we measure the current-phase relation and $dI/dV$ of a small Josephson junction and a carbon nanotube junction. In this latter case, in a regime where the nanotube is well conducting, we show that the non-sinusoidal current phase relation we find is consistent with the theory for a weak link, using the transmission extracted from the differential conductance in the normal state. This method holds great promise for future investigations of the current-phase relation of more exotic junctions.

9 pages, 11 figures

References in corpus (2)

• Supercurrent reversal in quantum dots
• Voltage-current and voltage-flux characteristics of asymmetric high TC DC SQUIDs

Cited by in corpus (8)

• The Anderson-Josephson quantum dot -- A theory perspective
• Manipulating the magnetic state of a carbon nanotube Josephson junction using the superconducting phase
• 0-$\pi$ quantum transition in a carbon nanotube Josephson junction: universal phase dependence and orbital degeneracy
• Washing out of the 0-pi transition in Josephson junctions
• Josephson response of a conventional and a noncentrosymmetric superconductor coupled via a double quantum dot
• Voltage noise, switching rates, and multiple phase-slips in moderately damped Josephson junctions
• Driving a Josephson Traveling Wave Parametric Amplifier into chaos: effects of a non-sinusoidal current-phase relation
• Supercurrent from the imaginary part of the Andreev levels in non-Hermitian Josephson junctions