Violet to near-infrared optical addressing of spin pairs in hexagonal boron nitride

TL;DR

This paper demonstrates the optical addressability and coherent control of spin pairs in hexagonal boron nitride across a broad wavelength range, highlighting its potential for quantum technology applications.

Contribution

It provides the first robust demonstration of optically addressable spin pairs in hBN with broadband emission and coherent control capabilities.

Findings

Spin pairs exist naturally in various hBN samples.

Spin pairs can be coherently controlled across violet to near-infrared wavelengths.

Optimal wavelengths for independent readout of spin pairs and defects are identified.

Abstract

Optically addressable solid-state spins are an important platform for practical quantum technologies. Van der Waals material hexagonal boron nitride (hBN) is a promising host as it contains a wide variety of optical emitters, but thus far observations of addressable spins have been sparse, and most of them lacked a demonstration of coherent spin control. Here we demonstrate robust optical readout of spin pairs in hBN with emission wavelengths spanning from violet to the near-infrared. We find these broadband spin pairs exist naturally in a variety of hBN samples from bulk crystals to powders to epitaxial films, and can be coherently controlled across the entire wavelength range. Furthermore, we identify the optimal wavelengths for independent readout of spin pairs and boron vacancy spin defects co-existing in the same sample. Our results establish the ubiquity of the optically addressable spin pair system in hBN across a broad parameter space, making it a versatile playground for spin-based quantum technologies.