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

BiQuTE Seminar committee

  • A. Giachero, A. Zaffaroni (Dip. Fisica)

  • F. Pezzoli (Dip. Scienze dei Materiali)

  • A. Leporati (Dip. di Informatica, Sistemistica e Comunicazione)

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
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)

Thursday September 22, 2022, 17:00 CEST

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

AdQuanta Group

We see our lab as a research accelerator – a place for developing new concepts and proof-of-concepts. Our research covers the entire spectrum from the fundamental all the way to the very applied. In particular, we strive to deepen our understanding of quantum science and make use of it:

Per Aspera Ad Quanta.

Quantum Optics with Free Electrons

Ido Kaminer
Department of Electrical and Computer Engineering
and Solid-State Institute
Technion – Israel Institute of Technology
Haifa, Israel

Monday September 26, 2022, 11:00 CEST

Aula Seminari, I Piano U5, Via Cozzi 55

Abstract and material

Until recently, work in quantum optics focused on light interacting with bound-electron systems such as atoms, quantum dots, and nonlinear optical crystals. In contrast, free-electron systems enable fundamentally different physical phenomena, as their energy distribution is continuous and not discrete, allowing for tunable transitions and selection rules. We have developed a platform for studying free-electron quantum optics at the nanoscale. We demonstrated the first features of this emerging field: observing the first coherent interaction of a free electron with a photonic cavity and with the quantum statistics of photons. These capabilities open new paths toward using free electrons as carriers of quantum information. Henceforth, free electrons emerge as quantum optical sources for photonics states used in fault-tolerant quantum computation and communication. Studies of quantum optics with free electrons suggest a new modality in electron microscopy: imaging coherence. This microscopy modality goes beyond conventional imaging of matter, to also image the quantum state of matter and quantum coherence of individual quantum systems.

  • N. Rivera and I. Kaminer, Light–matter interactions with photonic quasiparticles, Nature Reviews Physics 2, 538–561 (2020) (Review)

  • K. Wang, R. Dahan, M. Shentcis, Y. Kauffmann, A. Ben-Hayun, O. Reinhardt, S. Tsesses, I. Kaminer, Coherent Interaction between Free Electrons and Cavity Photons, Nature 582, 50 (2020)

  • R. Ruimy†, A. Gorlach†, C. Mechel, N. Rivera, and I. Kaminer, Towards atomic-resolution quantum measurements with coherently-shaped free electrons, Phys. Rev. Lett. 126, 233403 (2021)

  • O. Reinhardt†, C. Mechel†, M. H. Lynch, and I. Kaminer, Free-Electron Qubits, Annalen der Physik 533, 2000254 (2021)

  • Y. Kurman†, R. Dahan†, H. Herzig Shenfux, K. Wang, M. Yannai, Y. Adiv, O. Reinhardt, L. H. G. Tizei, S. Y. Woo, J. Li, J. H. Edgar, M. Kociak, F. H. L. Koppens, and I. Kaminer, Spatiotemporal imaging of 2D polariton wavepacket dynamics using free electrons, Science 372, 1181 (2021)

  • R. Dahan†, A. Gorlach†, U. Haeusler†, A. Karnieli†, O. Eyal, P. Yousefi, M. Segev, A. Arie, G. Eisenstein, P. Hommelhoff, and I. Kaminer, Imprinting the quantum statistics of photons on free electrons, Science 373, 6561 (2021)

  • A. Karnieli†, S. Tsesses†, R. Yu†, N. Rivera, Z. Zhao, A. Arie, S. Fan, and I. Kaminer‡, Quantum sensing of strongly coupled light-matter systems using free electrons, to appear in Science Advances

  • R. Dahan†, G. Baranes†, A. Gorlach, R. Ruimy, N. Rivera, and I. Kaminer, Creation of Optical Cat and GKP States Using Shaped Free Electrons, arxiv:2206.08828 (2022)

The CERN QTI: initial results and research perspective on Quantum Computing for HEP

Sofia Vallecorsa
CERN QTI Quantum Computing Coordinator
CERN, Geneva, Switzerland)

Friday October 14, 2022, 17:00 CEST

Abstract and material

In this context, a range of projects, set up at CERN in collaboration with HEP institutes worldwide, have explored the use of Quantum Computing, and Quantum Machine Learning algorithms, on different use cases which are representative of the next generation LHC experiments computing challenges. When reaching the end of the QTI second year, a set of preliminary results were gathered, outlining benefits, constraints and limitations of introducing quantum algorithms. These learnings will be used to feed into the definition of a long-term research plan, closely aligned with the technological development of quantum infrastructure. This talk will summarize the experience accumulated through the past years, outline the research results and provide an initial perspective of future directions.

slides - video recording