FETOPEN “SuperGate” funded with a €3M european project

From March 2021, SQEL is going to start a new research and innovation project SuperGate Gate Tuneable Superconducting Quantum Electronics, funded by the European Commission under the HORIZON-2020 FETOPEN program.

The project’s goal is to combine the powerful and energy-efficient superconductor technology with existing semiconductor technology and is based on the path-breaking discovery by the SQEL team that the superconductors can be controlled via electric field effect.

SuperGate is coordinated by the University of Konstanz and, apart from SQEL team institutes CNR-NANO and Scuola Normale Superiore di Pisa, involves CNR-SPIN, University of Salerno, Budapest University of Technology and Economics (HU), Delft University of Technology (NL), Chalmers University of Technology (SE) and SeeQC (IT).

The ultimate goal of SuperGate is to develop a new outperforming technology for superconducting logics that is completely based on electric field effect. The proposed technology promises a disruptive impact and radical transformations in the long term both in the world of supercomputing and concerning the design of innovative devices for quantum technologies.

Read more at the CNR-NANO press release.

“Digital Superconducting Quantum Machines” among the winners of “Start Cup Toscana”

Claudio Puglia collects the award for the project DSQM Claudio Puglia collects the award for the project DSQM

Digital superconducting quantum machines” (DSQM), an innovative project by SQEL researchers, is among the four winning projects of the “Start Cup Toscana 2020” an initiative that rewards the best innovative ideas born in the world of university research.

DSQM is the development of ultra-fast, low-power consumption superconducting circuits. This new frontier of information technology will contribute to the development of supercomputers 100 times faster than current ones. The project was developed by a team composed of Francesco Giazotto, Giorgio De Simoni, Elia Strambini, Federico Paolucci and Claudio Puglia from SQEL, Simone Gasparinetti (University of Chalmers) and Angelo Di Bernardo (University of Konstanz).

The technology of the DSQM project is based on the possibility of modifying the electrical current flowing in a superconductor through the application of an electric field. The team, ranked third in the competition, received a cash prize and the opportunity to participate to the “National Award for Innovation“, along with the other three awarded projects.

“Gate-Controlled Suspended Titanium Nanobridge Supercurrent Transistor” published on ACS Nano

"Gate-Controlled Suspended Titanium Nanobridge Supercurrent Transistor" published on ACS Nano “Gate-Controlled Suspended Titanium Nanobridge Supercurrent Transistor” published on ACS Nano

Under standard conditions, the electrostatic field-effect is negligible in conventional metals and was expected to be completely ineffective also in superconducting metals. This common belief was recently put under question by a family of experiments that displayed full gate-voltage-induced suppression of critical current in superconducting all-metallic gated nanotransistors.

A new research carried out at the SQEL add an another piece to this intriguing puzzle showing the control of the supercurrent in fully suspended superconducting nanobridges.

The research, published on ACS Nano by M. Rocci and co-authors, allows to take a different perspective compared to previous studies and promise a better understanding of the field effect in superconducting metals, ruling out some of the hypothesis as possible mechanisms driving for the observed phenomenology.

Press review of “A Josephson phase battery”

"A Josephson phase battery" has been featured on PhysicsWorld, LaRepubblica and others “A Josephson phase battery” has been featured on PhysicsWorld, LaRepubblica and others

We are very glad that our research work about the Josephson quantum phase battery (recently published on Nature Nanotechnology), raised a considerable interest in the past weeks and has been featured on the main national and international press.

You can find below some of the most relevant articles: check them out ad read what they are saying about us!

“A Josephson phase battery” has been published on “Nature Nanotechnology”

The first quantum phase battery, consisting of an indium arsenide (InAs) nanowire in contact with aluminum superconducting leads. Device concept by Andrea Iorio (SQEL). The first quantum phase battery, consisting of an indium arsenide (InAs) nanowire in contact with aluminum superconducting leads. Device concept by Andrea Iorio (SQEL).

A classical battery converts chemical energy into a persistent voltage bias that can power electronic circuits. Similarly, a phase battery is a quantum device that provides a persistent phase bias to the wave function of a quantum circuit. In a recent experiment carried out at SQEL, E. Strambini and co-workers have demonstrated and realized the first quantum phase battery in a hybrid superconducting circuit. The research, published on Nature Nanotechnology, is the result of an international collaboration which sees involved CNR-Nano, Scuola Normale Superiore, Salerno University in Italy and Material Physics Center (CFM), Donostia International Physics Center (DIPC) in Spain.

The quantum device that we realized is able to provide a persistent phase bias in a superconducting circuit effectively behaving like a quantum phase battery.

says Francesco Giazotto, group leader of SQEL.

The idea was first conceived in 2015, by Sebastian Bergeret and Ilya Tokatly, which proposed a theoretical system with the properties needed to build the phase battery. A few years later Francesco Giazotto and Elia Strambini from SQEL identified a suitable material combination, consisting of an n-doped InAs nanowire forming the core of the battery (the pile) and Al superconducting leads as poles and carried out the experiment at NEST Laboratory.

We found that the ferromagnetic polarization of the unpaired-spin states on the nanowire surface is efficiently converted into a persistent phase bias φ0 across the wire, leading to the anomalous Josephson effect. By applying an external in-plane magnetic field we achieved a continuous tuning of φ0 that persisted also in the absence of the field, thus realizing a phase battery.

comments Elia Strambini, first author of the research.

The next steps will consist in improving the control and performance of the battery by employing new material choices and design. This work contributes to the enormous advances being made in quantum technology that are expected to revolutionize both computing and sensing techniques, as well as medicine, and telecommunications in the near future.

More information:
Strambini, E., Iorio, A., Durante, O. et al. A Josephson phase battery. Nature Nanotechnology (2020). DOI: 10.1038/s41565-020-0712-7, www.nature.com/articles/s41565-020-0712-7