Seminars 2022

This series of informative seminars on quantum technologies has the goal of providing an introduction on the hottest topics in the field. The targeted audience includes students and non expert researchers.

Those who are interested to attend to the seminars are invited to subscribe the mailing list to receive the links to the video conference. Contacts: Angelo Nucciotti, Andrea Giachero

Organizers

  • Dipartimento di Fisica: A. Giachero, P. Govoni, A. Nucciotti, A. Zaffaroni

  • Dipartimento di Scienza dei Materiali:
    S. Sanguinetti, M. Fanciulli

  • Dipartimento di Informatica, Sistemistica e Informazione: A. Leporati, C. Ferretti

Breaking down the complexity of a superconducting quantum processor. An overview on the physics and engineering challenges to build and operate a QPU

Stefano Poletto
(Rigetti,
Director of Quantum Engineering, USA)

Friday May 20, 2022, 17:00 CEST

Abstract and material

Superconducting quantum processor units (QPUs) with qubit counting in the 10s to 100 are now commercially available from multiple companies and institutions. However, to build and operate a high performance superconducting QPU several physics and engineering challenges must be addressed. In this talk I will break down the complexity of a superconducting QPU, focusing on the single components and the interplay between them. I will start from a view of publicly available superconducting QPUs to gradually introduce the transmon qubit (the artificial atom), single-qubit manipulation, readout and on-chip filtering, coupling between qubits (fixed and tunable), and two-qubit gates. I will conclude with an overview of the Rigetti approach to scalability and the latest results on QPU performances

slides - video recording

An overview of quantum algorithms for near term quantum computation

Mattia Fiorentini
Head of Machine Learning and Quantum Algorithms
(Quantinuum / Cambridge Quantum,
Cambridge, England)

Friday May 27, 2022, 17:00 CEST

Abstract and material

The current generation of quantum computers comprises universally programmable hardware but suffers from sub-optimal control, limited memory, and inefficient input-output operations. Nevertheless a burgeoning research activity led by practical experimentation has led to new algorithms that can mitigate some of the current inconveniences. Quantum Machine Learning is one of such new approaches and has enabled both researchers and practitioners to apply quantum computation to new domains. In my talk, I will introduce Quantum Machine Learning and some of its applications as well as current open problems. Lastly I will touch upon other quantum algorithms types that may become relevant for next generation hardware.

video recording (DISCLAIMER: "Cambridge Quantum" (CQ) and "Quantinuum" logos cannot be reused without authorization from the respective owners. Although this talk discusses topics of interest to Quantinuum, any view or comment expressed by Mattia Fiorentini are his own)

Next-generation quantum-limited amplifiers for superconducting quantum computing

José Aumentado
Advanced Microwave Photonics Group
(NIST, Boulder, USA)

Friday June 3, 2022, 17:00 CEST
TBD

Abstract and material

Josephson parametric amplifiers have played an critical role in making superconducting quantum computing seem remotely viable. However, for many physicists involved in this work, these amplifiers can seem like a pragmatic (but necessary) afterthought. In this talk, I'll motivate why it's necessary to continue to develop these devices, explain the basics of parametric coupling, and how we've applied multimode linear coupled mode theory to create a new generation of parametric amplifiers. These amplifiers demonstrate useful properties for qubit measurement, including directionality (nonreciprocity), phase-sensitive gain, and nearly quantum-limited noise performance. If time permits, I’ll discuss how we’ve leveraged these techniques approaching ideal efficiency in qubit state measurement.

slides - video recording