We experimentally demonstrate that the decoherence of a spin by a spin bath can be completely eliminated by fully polarizing the spin bath. We use electron paramagnetic resonance at 240 gigahertz and 8 Tesla to study the spin coherence time T2 of nitrogen-vacancy centers and nitrogen impurities in diamond from room temperature down to 1.3 K. A sharp increase of T2 is observed below the Zeeman energy (11.5 K). The data are well described by a suppression of the flip-flop induced spin bath fluctuations due to thermal spin polarization. T2 saturates at ∼250μs below 2 K, where the spin bath polarization is 99.4 %.
@article{arxiv.0804.1537,
title = {Quenching Spin Decoherence in Diamond through Spin Bath Polarization},
author = {Susumu Takahashi and Ronald Hanson and Johan van Tol and Mark S. Sherwin and David D. Awschalom},
journal= {arXiv preprint arXiv:0804.1537},
year = {2009}
}