research

We design, microfabricate and measure superconducting devices based on different circuit elements, from Josephson junctions to high kinetic inductance lines. We use these devices both for fundamental physics (e.g. cQED experiments) and application-oriented projects (e.g. quantum-limited read-out systems).

Josephson junctions-based devices are at the core of our research activities. The Josephson junction is the elementary building block that we exploit to build more advanced devices, such as superconducting qubits, superconducting parametric amplifiers and high-sensitivity magnetometers. We are developing Josephson junctions based on Al/AlOx/Al and Nb/Al-AlOx/Nb stacks, exploiting vertical microfabrication processes. 

Travelling Wave Parametric amplifiers (TWPAs) are superconducting devices based on non-linear effects achieved with arrays of Josephson junctions or disordered superconductors characterised by highly non-linear kinetic inductance. TWPAs are crucial to reach ultralow-noise amplification - potentially approaching the quantum noise limit - in qubit read-out systems. Moreover, TWPAs can be exploited for the generation of microwave entangled photons and microwave squeezing. 

Tunable resonators are versatile circuits which can serve as platform for cQED and quantum optics experiments as well as quantum sensing applications. We are developing both Josephson-junctions-based and kinetic-inductance-based tunable resonators for a variety of projects. For example, we are working on Kinetic Inductance Current Sensors for multiplexed read-out of cryogenic sensors and we have a pending patent on an innovative superconducting device for microwave pulse control.

Collaborators

The FBK SQ team is fruitfully collaborating 

• on a local level within the Quantum Community in Trento - Q@Tn and with the CNR Cryo Quantum Lab

  • Theorists: Iacopo Carusotto (CNR-INO Trento), Gianluca Rastelli (CNR-INO Trento), and collaborators

  • Experimentalists: Andrea Vinante (CNR-IFN Trento), Paolo Falferi (CNR-IFN Trento), Renato Mezzena (University of Trento)

• on a national level with INFN, University of Milano Bicocca, INRiM, CNR, University of Padova

• on an international level, e.g. with SQC group at Neel Institute, Grenoble (France), Aalto University (Finland), VTT (Finland), NIST (US), IMRE (Singapore), CERN (Switzerland)