We demonstrate optically detected spin resonance of a single electron confined to a self-assembled quantum dot. The dot is rendered dark by resonant optical pumping of the spin with a coherent laser. Contrast is restored by applying a radio frequency (rf) magnetic field at the spin resonance. The scheme is sensitive even to rf fields of just a few micro-T. In one case, the spin resonance behaves exactly as a driven 3-level quantum system (a lambda-system) with weak damping. In another, the dot exhibits remarkably strong (67% signal recovery) and narrow (0.34 MHz) spin resonances with fluctuating resonant positions, evidence of unusual dynamic processes of non-Markovian character.
@article{arxiv.0710.4901,
title = {Optical detection of single electron spin resonance in a quantum dot},
author = {Martin Kroner and Kathrina M. Weiss and Benjamin Biedermann and Stefan Seidl and Stefan Manus and Alexander Holleitner and Antonio Badolato and Pierre M. Petroff and Brian D. Gerardot and Richard J. Warburton and Khaled Karrai},
journal= {arXiv preprint arXiv:0710.4901},
year = {2009}
}