QSE Quantum Seminar: Low-overhead fault-tolerant quantum computing using cat qubits


Event details

Date 30.04.2024
Hour 12:0013:30
Speaker Jérémie Guillaud
Category Conferences - Seminars
Event Language English

Please join us for the QSE Center Quantum Seminar with Dr. Jérémie Guillaud from Alice & Bob, who will give the talk "Low-overhead fault-tolerant quantum computing using cat qubits" on Thursday April 30.
Location: CE 1 100

Pizzas will be available before the seminar at 12:00. All PhDs, postdocs, students, and PIs are welcome to join us.

TITLE: Low-overhead fault-tolerant quantum computing using cat qubits

ABSTRACT: A significant number of applications envisioned for quantum computing typically require applying on the order of one million to one trillion quantum gates on 100 to 10,000 algorithmic qubits, which is beyond the reach of current machines, limited to a few thousand gates on a few hundred qubits at most. While quantum error correction (QEC) theoretically solves this problem, the practical implementation of QEC protocols implies a significant material cost: typically, the total number of qubits is multiplied by 1,000. The monumental task of building a quantum computer with several million qubits has motivated the rise of new 'hardware efficient' approaches, which allow for the implementation of error correction without exploding the size of the necessary material resources.

In this talk, I will present the cat qubit architecture developed by Alice&Bob. Cat qubits are part of the family of bosonic codes, where quantum information is encoded in the infinite-dimensional Hilbert space of a quantum harmonic oscillator. Thanks to the encoding of the cat qubit, one of the two quantum errors (bit-flips) is exponentially suppressed with the 'size' of the cat qubit. In a way, this simplifies the problem of quantum error correction to that of classical error correction. I will first present the LDPC-cat quantum computer architecture theoretically proposed by Alice&Bob in collaboration with Inria . Then, I will present and comment recent experimental progress around cat qubits, to give an idea of the current state of the hardware and the time scales necessary for the realisation of large-scale quantum computing.

Jérémie Guillaud is currently the Chief of Theory at Alice & Bob. Jérémie was previously a PhD student at Inria from September 2017 to September 2020. Jérémie was also a research intern at Inria from February 2017 to July 2017, working on the development of modular architecture for quantum information processing. From March 2016 to August 2016, they were a research intern at the University of Melbourne, studying and developing max-plus methods applied to optimal time stopping problems. Jérémie Guillaud has also been treasurer at X-MicroFinance from September 2015 to August 2016, where they supervised the loan campaign in Guatemala and was in charge of the relation with the financial partners in France. Prior to that, they were an analyst intern at Societe Generale Corporate and Investment Banking - SGCIB from June 2015 to August 2015. Jérémie Guillaud received their engineer's degree in applied mathematics from École Polytechnique. Jérémie then went on to earn their master's degree in applied mathematics from Pierre and Marie Curie University. Finally, they earned their doctor of philosophy in quantum computing from Ecole normale supérieure.

Practical information

  • General public
  • Free


  • QSE Center


QSE Quantum Seminar