QSE Quantum Seminars: Denis Seletskiy and Cornelius Hempel


Event details

Date 07.12.2023
Hour 11:3013:15
Speaker Denis Seletskiy Cornelius Hempel
Category Conferences - Seminars
Event Language English

Please join us for the QSE Center Quantum Seminar with Prof. Denis Seletskiy from Polytechnique Montreal and Dr. Cornelius Hempel from Paul Scherrer Institute (PSI), who will speak on Thursday, December 7, about “Experimental quantum electrodynamics” and "Trapped ion quantum computers and the challenge of scaling ", respectively. 

Location: BS 270

Prof. Denis Seletskiy's talk: 11:30-12:15
Dr. Cornelius Hempel 's talk: 12:30- 13:15
Pizzas will be available in between the seminars at 12:15. All PhDs, postdocs, students, and PIs are welcome to join us.

TITLE: Experimental quantum electrodynamics

Traditional approaches to quantum optics are rooted in the reciprocal, frequency-momentum space. In this talk, I will discuss recent advances toward sub-cycle quantum optics, where, instead, quantum fields are accessed in a localized region of space-time [1-2]. Both regimes will be compared side-by-side to contrast the advantages of each approach, with a particular emphasis on quantum sensing proposals [3-5] in the mid-infrared frequency range.
In the concluding part of the talk, I will summarize recent advances in producing few-cycle bright one- and two-mode squeezed vacuum states in a single few-cycle temporal mode with macroscopic photon occupation [6]. Such capabilities are poised to unlock a new era of (extreme) nonlinear quantum optics in the attosecond regime [7].[1] Direct sampling of electric-field vacuum fluctuations
C. Riek et al., Science 350, 420-423 (2015)
[2] Electric field correlation measurements on the electromagnetic vacuum state
I-C Benea-Chelmus et al., Nature 568, 202-206 (2019)
[3] Enhanced electro-optic sampling with quantum probes
Stéphane Virally, Patrick Cusson, DVS, Phys. Rev. Lett. 127, 270504 (2021)
[4] Self-referenced subcycle metrology of quantum fields
S. Gündoğdu et al, Laser Phot. Rev. 17, 2200706 (2023)
[5] Direct measurement of Husimi-Q function of electric field in time-domain
Sho Onoe, Stéphane Virally, DVS, arXiv:2307.13088 (2023)
[6] Twin beam probe pulses for subcycle sampling of mid-IR quantum fields
Patrick Cusson; Stéphane Virally; DVS, IRMMW-THz Conference, paper Th-PM2-5-7 (2023)
[7] 2023 Nobel Prize in Physics: Pierre Agostini, Ferenc Krausz and Anne L’Huillier. Experimental methods that generate attosecond pulses for studying electron dynamics in matter.

Denis Seletskiy is an Associate Professor of Engineering Physics and a holder of Canada Research Chair (Tier 2) in “Ultrafast and Quantum Photonics” at Polytechnique Montreal. He received his PhD from the Optical Sciences and Engineering program at the University of New Mexico in 2010, followed by a National Research Council postdoctoral fellowship at Air Force Research Laboratories (2010-2012) and a 5-year junior group leader position and Marie Curie Zukuntskolleg Research fellowship at the University of Konstanz, Germany. In 2017 Seletskiy established the femtoQ laboratory at Polytechnique, which is focused on advancing theory, laser technology, and metrology protocols for time-domain quantum photonics. Since October 2022, he is leading an EU-CAN consortium in Mid-Infrared Quantum Technologies for Sensing (MIRAQLS).

TITLE: Trapped ion quantum computers and the challenge of scaling 

Trapped ions provide an excellent platform for quantum science experiments with leading performance metrics in fidelities, coherence times and quantum volume. While qubits are identical, a major challenge of the platform is scalability, i.e. extending the same level of control over larger numbers of qubits. Work in this direction has been going on for a number of years already and promising avenues have been identified that pave the way to realizing a large scale error corrected quantum computer.

In this talk, I will provide a brief introduction to the trapped-ion architecture, showcase some high profile results in quantum simulation and computation, including the only demonstration so-far of active quantum error correction. I will then focus on the scaling aspect, which is at the core of our groups mission at PSI, where we investigate integrated photonics for light delivery and modulation.
Cornelius Hempel leads the Ion Trap Quantum Computation team at the ETH Zürich-PSI Quantum Computing Hub located at the Paul Scherrer Institute (PSI). He obtained his PhD in Physics in the group of Prof. Rainer Blatt at the University of Innsbruck (Austria) in 2014 and previously Masters and Diplom degrees at the University of Michigan (USA) and Martin Luther University Halle (Germany). Following a short postdoc at the Institut for Quantum Optics and Quantum Information (IQOQI), he moved to the University of Sydney (Australia) as a Research Fellow in 2016 and in 2018 became principal investigator in the ytterbium laboratory of the Quantum Control Laboratory. He was promoted to Senior Research Fellow (equivalent to research associate professor in the US) in 2020. He continues to hold an honorary position in Australia since his move to Switzerland in 2021.

Practical information

  • General public
  • Free


  • QSE Center


QSE Quantum Seminar