[Qubits de chat pour le calcul quantique]
Le développement des circuits quantiques Josephson a généré de grands espoirs pour le traitement fiable de l'information quantique. Alors que ces progrès se sont accompagnés de diverses expériences de principe sur des systèmes quantiques de petites tailles, il faut désormais franchir l'étape importante du passage à l'échelle supérieure en nombre de qubits pour les protocoles. Le calcul tolérant aux erreurs avec des qubits logiques protégés est cependant habituellement envisagé au prix d'un significatif surcoût en ressources matérielles. Chacun des qubits physiques impliqués devra par ailleurs toujours disposer de caractéristiques optimales (temps de cohérence, force de couplage et accordabilité). Ici, et dans le but d'explorer des approches alternatives pour dépasser ces obstacles, je passe en revue un ensemble de propositions théoriques récentes et les premières expériences correspondantes, qui rentrent dans un paradigme de protection de mémoire quantique et de calcul quantique universel qui reste peu gourmand en ressources matérielles.
The development of quantum Josephson circuits has created a strong expectation for reliable processing of quantum information. While this progress has already led to various proof-of-principle experiments on small-scale quantum systems, a major scaling step is required towards many-qubit protocols. Fault-tolerant computation with protected logical qubits usually comes at the expense of a significant overhead in the hardware. Each of the involved physical qubits still needs to satisfy the best achieved properties (coherence times, coupling strengths and tunability). Here, and in the aim of addressing alternative approaches to deal with these obstacles, I overview a series of recent theoretical proposals, and the experimental developments following these proposals, to enable a hardware-efficient paradigm for quantum memory protection and universal quantum computation.
Mot clés : Calcul quantique universel, Mémoire quantique, Correction des erreurs quantiques, États du chat de Schrödinger, Circuits quantiques supraconducteurs
Mazyar Mirrahimi 1, 2
@article{CRPHYS_2016__17_7_778_0,
author = {Mazyar Mirrahimi},
title = {Cat-qubits for quantum computation},
journal = {Comptes Rendus. Physique},
pages = {778--787},
publisher = {Elsevier},
volume = {17},
number = {7},
year = {2016},
doi = {10.1016/j.crhy.2016.07.011},
language = {en},
}
Mazyar Mirrahimi. Cat-qubits for quantum computation. Comptes Rendus. Physique, Volume 17 (2016) no. 7, pp. 778-787. doi : 10.1016/j.crhy.2016.07.011. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2016.07.011/
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Cité par Sources :
☆ This paper, written in March 2015, is an overview of recent proposals and experiments for encoding, protecting and manipulating quantum information in so-called Schrödinger cat states of a quantum harmonic oscillator. The author acknowledges the collaboration and discussions with Zaki Leghtas, Michel H. Devoret, Robert J. Schoelkopf, and Liang Jiang, as well as many other collaborators at Yale University, the group of Benjamin Huard at the École Normale Supèrieure and the Quantronics group at CEA Saclay.
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