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arXiv · 1910.08741

Native three-body interaction in superconducting circuits

Simon Panyella Pedersen·Kasper Sangild Christensen·Nikolaj Thomas Zinner
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Abstract

We show how a superconducting circuit consisting of three identical, non-linear oscillators in series considered in terms of its electrical modes can implement a strong, native three-body interaction among qubits. Because of strong interactions, part of the qubit-subspace is coupled to higher levels. The remaining qubit states can be used to implement a restricted Fredkin gate, which in turn implements a CNOT-gate or a spin transistor. Including non-symmetric contributions from couplings to ground and external control we alter the circuit slightly to compensate, and find average fidelities for our implementation of the above gates above $ 99.5\% $ with operation times on the order of a nanosecond. Additionally we show how to analytically include all orders of the cosine contributions from Josephson junctions to the Hamiltonian of a superconducting circuit.

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Simon Panyella Pedersen, Kasper Sangild Christensen, Nikolaj Thomas Zinner. 2019-10-19. Native three-body interaction in superconducting circuits. https://doi.org/10.1103/physrevresearch.1.033123

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