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arXiv · 1610.07915

Implementation of pairwise longitudinal coupling in a three-qubit superconducting circuit

Tanay Roy·Suman Kundu·Madhavi Chand·Sumeru Hazra·N. Nehra·R. Cosmic·A. Ranadive·Meghan P. Patankar·Kedar Damle·R. Vijay
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Abstract

We present the "trimon", a multi-mode superconducting circuit implementing three qubits with all-to-all longitudinal coupling. This always-on interaction enables simple implementation of generalized controlled-NOT gates which form a universal set. Further, two of the three qubits are protected against Purcell decay while retaining measurability. We demonstrate high-fidelity state swapping operations between two qubits and characterize the coupling of all three qubits to a neighbouring transmon qubit. Our results offer a new paradigm for multi-qubit architecture with applications in quantum error correction, quantum simulations and quantum annealing.

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Tanay Roy, Suman Kundu, Madhavi Chand, Sumeru Hazra, N. Nehra, R. Cosmic, A. Ranadive, Meghan P. Patankar, Kedar Damle, R. Vijay. 2016-10-25. Implementation of pairwise longitudinal coupling in a three-qubit superconducting circuit. https://doi.org/10.1103/physrevapplied.7.054025

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