Mapping a 50-spin-qubit network through correlated sensing

TL;DR

This paper demonstrates high-resolution mapping of a 50-spin network using a single nitrogen-vacancy center in diamond, advancing quantum sensing and network characterization capabilities.

Contribution

The authors develop concatenated double-resonance sequences for correlated sensing, enabling detailed mapping of large spin networks with high spectral resolution.

Findings

Mapped a 50-spin network with high spectral resolution

Identified spin-chains and their interconnections

Enhanced potential for quantum simulation and nano-scale imaging

Abstract

Spins associated to optically accessible solid-state defects have emerged as a versatile platform for exploring quantum simulation, quantum sensing and quantum communication. Pioneering experiments have shown the sensing, imaging, and control of multiple nuclear spins surrounding a single electron-spin defect. However, the accessible size of these spin networks has been constrained by the spectral resolution of current methods. Here, we map a network of 50 coupled spins through high-resolution correlated sensing schemes, using a single nitrogen-vacancy center in diamond. We develop concatenated double-resonance sequences that identify spin-chains through the network. These chains reveal the characteristic spin frequencies and their interconnections with high spectral resolution, and can be fused together to map out the network. Our results provide new opportunities for quantum simulations by increasing the number of available spin qubits. Additionally, our methods might find applications in nano-scale imaging of complex spin systems external to the host crystal.