We investigate the erbium flip-flop dynamics as a limiting factor of the electron spin lifetime and more generally as an indirect source of decoherence in rare-earth doped insulators. Despite the random isotropic arrangement of dopants in the host crystal, the dipolar interaction strongly depends on the magnetic field orientation following the strong anisotropy of the g-factor. In Er3+:Y2SiO5, we observe by transient optical spectroscopy a three orders of magnitude variation of the erbium flip-flop rate (10ppm dopant concentration). The measurements in two different samples, with 10ppm and 50ppm concentrations, are well-supported by our analytic modeling of the dipolar coupling between identical spins with an anisotropic g-tensor. The model can be applied to other rare-earth doped materials. We extrapolate the calculation to Er3+:CaWO4, Er3+:LiNbO3 and Nd3+:Y2SiO5 at different concentrations.
@article{arxiv.1811.10285,
title = {Optical study of the anisotropic erbium spin flip-flop dynamics},
author = {B. Car and L. Veissier and A. Louchet-Chauvet and J. -L. Le Gouët and T. Chanelière},
journal= {arXiv preprint arXiv:1811.10285},
year = {2019}
}