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arXiv · 2303.03541

Gottesman-Kitaev-Preskill state preparation using periodic driving

Xanda C. Kolesnikow·Raditya Weda Bomantara·Andrew C. Doherty·Arne L. Grimsmo
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Abstract

The Gottesman-Kitaev-Preskill (GKP) code may be used to overcome noise in continuous variable quantum systems. However, preparing GKP states remains experimentally challenging. We propose a method for preparing GKP states by engineering a time-periodic Hamiltonian whose Floquet states are GKP states. This Hamiltonian may be realized in a superconducting circuit comprising a SQUID shunted by a superinductor and a capacitor, with a characteristic impedance twice the resistance quantum. The GKP Floquet states can be prepared by adiabatically tuning the frequency of the external magnetic flux drive. We predict that highly squeezed $>11.9$ dB ($10.8$ dB) GKP magic states can be prepared on a microsecond timescale, given a quality factor of $10^6$ ($10^5$) and flux noise at typical rates.

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Xanda C. Kolesnikow, Raditya Weda Bomantara, Andrew C. Doherty, Arne L. Grimsmo. 2023-03-06. Gottesman-Kitaev-Preskill state preparation using periodic driving. https://doi.org/10.1103/physrevlett.132.130605

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