A programmable three-qubit superconducting processor with all-to-all connectivity

TL;DR

This paper introduces a programmable three-qubit superconducting processor with all-to-all connectivity, enabling efficient implementation of complex quantum algorithms and demonstrating its potential as a scalable quantum computing building block.

Contribution

The work presents a novel three-qubit superconducting processor with strong all-to-all coupling and native three-qubit gates, surpassing limitations of nearest-neighbor architectures.

Findings

Successfully implemented three-qubit algorithms like Deutsch-Jozsa, Bernstein-Vazirani, Grover's search, and quantum Fourier transform.

Demonstrated high-fidelity three-qubit gate operations.

Showcased potential for scalable quantum systems with enhanced connectivity.

Abstract

Superconducting circuits are at the forefront of quantum computing technology because of the unparalleled combination of good coherence, fast gates and flexibility in design parameters. The majority of experiments demonstrating small quantum algorithms in the superconducting architecture have used transmon qubits and transverse qubit-qubit coupling. However, efficient universal digital computing has remained a challenge due to the fact that majority of the state-of-art architectures rely on nearest-neighbor coupling in one or two dimensions. The limited connectivity and the availability of only two-qubit entangling gates result in inefficient implementation of algorithms with reduced fidelity. In this work, we present a programmable three-qubit processor, nicknamed "trimon", with strong all-to-all coupling and access to native three-qubit gates. We implement three-qubit version of various algorithms, namely Deutsch-Jozsa, Bernstein-Vazirani, Grover's search and the quantum Fourier transform, to demonstrate the performance of our processor. Our results show the potential of the trimon as a building block for larger systems with enhanced qubit-qubit connectivity.