Benefiting from both molecular tunability and versatile methods for deployment, optically interfaced molecular spins are a promising platform for quantum technologies such as sensing and imaging. Room-temperature optically detected coherent spin control is a key enabler for many applications, combining sensitive readout, versatile spin manipulation, and ambient operation. Here we demonstrate such functionality in a molecular spin system. Using the photoexcited triplet state of organic chromophores (pentacene doped in a para-terphenyl host), we optically detect coherent spin manipulation with photoluminescence contrasts exceeding 10% and microsecond coherence times at room temperature. We further demonstrate how coherent control of multiple triplet sublevels can significantly enhance optical spin contrast, and extend optically detected coherent control to a thermally evaporated thin film, retaining high photoluminescence contrast and coherence times of order one microsecond. These results open opportunities for room-temperature quantum technologies that can be systematically tailored through synthetic chemistry.
@article{arxiv.2402.07572,
title = {Room-temperature optically detected coherent control of molecular spins},
author = {Adrian Mena and Sarah K. Mann and Angus Cowley-Semple and Emma Bryan and Sandrine Heutz and Dane R. McCamey and Max Attwood and Sam L. Bayliss},
journal= {arXiv preprint arXiv:2402.07572},
year = {2024}
}