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arXiv:1002.1394 · Physical Review Letters

Superconducting Resonators as Beam Splitters for Linear-Optics Quantum Computation

Luca Chirolli, Guido Burkard, Shwetank Kumar, David Peter Divincenzo

Published Jun 8, 2010• 35 citations
arXivHTMLPDF

Abstract

We propose and analyze a technique for producing a beam-splitting quantum gate between two modes of a ring-resonator superconducting cavity. The cavity has two integrated superconducting quantum interference devices (SQUIDs) that are modulated by applying an external magnetic field. The gate is accomplished by applying a radio frequency pulse to one of the SQUIDs at the difference of the two mode frequencies. Departures from perfect beam splitting only arise from corrections to the rotating wave approximation; an exact calculation gives a fidelity of >0.9992. Our construction completes the toolkit for linear-optics quantum computing in circuit quantum electrodynamics.

DOI
10.1103/physrevlett.104.230502

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