title: Superconducting quantum interference devices based set-up for probing current noise and correlations in three-terminal devices.
abstract: We have implemented a new experimental set-up for precise measurements of current fluctuations in three-terminal devices. The system operates at very low temperatures (30 mK) and is equipped with three superconducting quantum interference devices (SQUIDs) as low noise current amplifiers. A SQUID input coil is connected to each terminal of a sample allowing the acquisition of time-dependent current everywhere in the circuit. From these traces, we can measure the current mean value, the noise, and cross-correlations between different branches of a device. In this paper, we present calibration results of noise and cross-correlations obtained using low impedance macroscopic resistors. From these results, we can extract the noise level of the set-up and show that there are no intrinsic correlations due to the measurement scheme. We also studied noise and correlations as a function of a dc current and estimated the electronic temperature of various macroscopic resistors.
authors.affiliation: SPSMS/LaTEQS, UMR-E 9001, CEA-INAC, and Université Joseph Fourier, Grenoble, France.
authors.forename: A H
authors.initials: AH
authors.lastname: Pfeffer
authors.forename: B
authors.initials: B
authors.lastname: Kaviraj
authors.forename: O
authors.initials: O
authors.lastname: Coupiac
authors.forename: F
authors.initials: F
authors.lastname: Lefloch