Parametric amplification by coupled flux qubits

M. Rehak; P. Neilinger; M. Grajcar; G. Oelsner; U. Hubner; E. Ilichev; H. -G. Meyer

doi:10.1063/1.4873719

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arXiv · 1312.7237

Parametric amplification by coupled flux qubits

M. Rehak·P. Neilinger·M. Grajcar·G. Oelsner·U. Hubner·E. Ilichev·H. -G. Meyer

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Abstract

We report the parametric amplification of a microwave signal in a Kerr medium formed from superconducting qubits. Two mutually coupled flux qubits, embedded in the current antinode of a superconducting coplanar waveguide resonator, are used as a nonlinear element. Shared Josephson junctions provide the qubit-resonator coupling, resulting in a device with a measured gain of about 20 dB. We argue, that this arrangement represents a unit cell which can be straightforwardly extended to a quasi one-dimensional quantum metamaterial with a large tunable Kerr nonlinearity.

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M. Rehak, P. Neilinger, M. Grajcar, G. Oelsner, U. Hubner, E. Ilichev, H. -G. Meyer. 2013-12-27. Parametric amplification by coupled flux qubits. https://doi.org/10.1063/1.4873719

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