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arXiv · 1711.01658

Multi-mode superconducting circuits for realizing strongly coupled multi-qubit processor units

Tanay Roy·Madhavi Chand·Anirban Bhattacharjee·Sumeru Hazra·Suman Kundu·Kedar Damle·R. Vijay
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Abstract

Inter-qubit coupling and qubit connectivity in a processor are crucial for achieving high fidelity multi-qubit gates and efficient implementation of quantum algorithms. Typical superconducting processors employ relatively weak transverse inter-qubit coupling which are activated via frequency tuning or microwave drives. Here, we propose a class of multi-mode superconducting circuits which realize multiple transmon qubits with all-to-all longitudinal coupling. These "artificial molecules" directly implement a multi-dimensional Hilbert space that can be easily manipulated due to the always-on longitudinal coupling. We describe the basic technique to analyze such circuits, compute the relevant properties and discuss how to optimize them to create efficient small-scale quantum processors with universal programmability.

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Tanay Roy, Madhavi Chand, Anirban Bhattacharjee, Sumeru Hazra, Suman Kundu, Kedar Damle, R. Vijay. 2017-11-05. Multi-mode superconducting circuits for realizing strongly coupled multi-qubit processor units. https://doi.org/10.1103/physreva.98.052318

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