Superconducting qubit network with controllable nearest neighbor coupling

TL;DR

This paper proposes a scalable superconducting qubit network with controllable nearest-neighbor coupling using Josephson junctions, enabling universal quantum gate operations at the charge degeneracy point.

Contribution

It introduces a novel design of a superconducting qubit network with switchable coupling, applicable to charge and charge-phase qubits, enhancing quantum computing scalability.

Findings

Achieves switchable nearest-neighbor coupling via Josephson junctions.

Supports universal quantum gate operations at charge degeneracy point.

Integrates qubit readout and coupling mechanisms in the same architecture.

Abstract

We investigate the design and functionality of a network of loop-shaped charge qubits with switchable nearest-neighbor coupling. The qubit coupling is achieved by placing large Josephson junctions at the intersections of the qubit loops and selectively applying bias currents. The network is scalable and makes it possible to perform a universal set of quantum gates. The coupling scheme allows gate operation at the charge degeneracy point of each qubit, and also applies to charge-phase qubits. Additional Josephson junctions included in the qubit loops for qubit readout can also be employed for qubit coupling.