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arXiv · 2110.06102

Spin echo from erbium implanted silicon

Abstract

Erbium implanted silicon as a quantum technology platform has both telecommunications and integrated circuit processing compatibility. In Si implanted with Er to a concentration of 3x10^17 cm^3 and O to a concentration of 10^20 cm^3, the electron spin coherence time, T2, and the spin-lattice relaxation time, T1, were measured to be 7.5 ls and ~1 ms, respectively, at 5 K. The spin echo decay profile displayed strong modulation, which was consistent with the super-hyperfine interaction between Er3þ and a spin bath of 29Si nuclei. The calculated spectral diffusion time was similar to the measured T2, which indicated that T2 was limited by spectral diffusion due to T1-induced flips of neighboring Er3þ spins. The origin of the echo is an Er center surrounded by six O atoms with monoclinic C1h site symmetry.

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Mark A. Hughes, Naitik A. Panjwani, Matias Urdampilleta, Kevin P. Homewood, Ben Murdin, J. David Carey. 2021-10-12. Spin echo from erbium implanted silicon. https://doi.org/10.1063/5.0046904

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