Coherent dressing of a quantum two-level system provides access to a new quantum system with improved properties - a different and easily tuneable level splitting, faster control, and longer coherence times. In our work we investigate the properties of the dressed, donor-bound electron spin in silicon, and probe its potential for the use as quantum bit in scalable architectures. The two dressed spin-polariton levels constitute a quantum bit that can be coherently driven with an oscillating magnetic field, an oscillating electric field, by frequency modulating the driving field, or by a simple detuning pulse. We measure coherence times of T2ρ∗=2.4 ms and T2ρHahn=9 ms, one order of magnitude longer than those of the undressed qubit. Furthermore, the use of the dressed states enables coherent coupling of the solid-state spins to electric fields and mechanical oscillations.
@article{arxiv.1603.04800,
title = {A Dressed Spin Qubit in Silicon},
author = {Arne Laucht and Rachpon Kalra and Stephanie Simmons and Juan P. Dehollain and Juha T. Muhonen and Fahd A. Mohiyaddin and Solomon Freer and Fay E. Hudson and Kohei M. Itoh and David N. Jamieson and Jeffrey C. McCallum and Andrew S. Dzurak and A. Morello},
journal= {arXiv preprint arXiv:1603.04800},
year = {2016}
}