A CNOT gate between multiphoton qubits encoded in two cavities

Serge Rosenblum 1 Yvonne Gao 1 Philip Reinhold 1 Chen Wang 1 Christopher Axline 1 Luigi Frunzio 1 Steven Girvin 1 Liang Jiang 1 Mazyar Mirrahimi 2 Michel Devoret 1 Robert Schoelkopf 1
2 QUANTIC - QUANTum Information Circuits
ENS Paris - École normale supérieure - Paris, UPMC - Université Pierre et Marie Curie - Paris 6, MINES ParisTech - École nationale supérieure des mines de Paris, Inria de Paris
Abstract : Entangling gates between qubits are a crucial component for performing algorithms in quantum computers. However, any quantum algorithm will ultimately have to operate on error-protected logical qubits, which are effective qubits encoded in a high-dimensional Hilbert space. A common approach is to encode logical qubits in collective states of multiple two-level systems, but algorithms operating on multiple logical qubits are highly complex and have not yet been demonstrated. Here, we experimentally realize a controlled NOT (CNOT) gate between two multiphoton qubits in two microwave cavities. In this approach, we encode a qubit in the large Hilbert space of a single cavity mode, rather than in multiple two-level systems. We couple two such encoded qubits together through a transmon, which is driven with an RF pump to apply the CNOT gate within 190 ns. This is two orders of magnitude shorter than the decoherence time of any part of the system, enabling high-fidelity operations comparable to state-of-the-art gates between two-level systems. These results are an important step towards universal algorithms on error-corrected logical qubits.
Type de document :
Pré-publication, Document de travail
10 pages, 11 figures (incl. Supplementary Information). 2017
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Contributeur : Mazyar Mirrahimi <>
Soumis le : jeudi 30 novembre 2017 - 16:31:58
Dernière modification le : mardi 12 décembre 2017 - 10:44:20


  • HAL Id : hal-01652773, version 1
  • ARXIV : 1709.05425



Serge Rosenblum, Yvonne Gao, Philip Reinhold, Chen Wang, Christopher Axline, et al.. A CNOT gate between multiphoton qubits encoded in two cavities. 10 pages, 11 figures (incl. Supplementary Information). 2017. 〈hal-01652773〉



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