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arXiv · 1811.10285

Optical study of the anisotropic erbium spin flip-flop dynamics

B. Car·L. Veissier·A. Louchet-Chauvet·J. -L. Le Gouët·T. Chanelière
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Abstract

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 Er$^{3+}$:Y$_2$SiO$_5$, 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 Er$^{3+}$:CaWO$_4$, Er$^{3+}$:LiNbO$_3$ and Nd$^{3+}$:Y$_2$SiO$_5$ at different concentrations.

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B. Car, L. Veissier, A. Louchet-Chauvet, J. -L. Le Gouët, T. Chanelière. 2018-11-26. Optical study of the anisotropic erbium spin flip-flop dynamics. https://doi.org/10.1103/physrevb.100.165107

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