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arXiv · 2501.03348

Ab initio calculations of erbium crystal field splittings in oxide hosts

Yogendra Limbu·Yueguang Shi·Joseph Sink·Tharnier O. Puel·Durga Paudyal·Michael E. Flatté
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Abstract

We present an effective ab initio method to calculate the crystal field coefficients of an erbium (Er3+) ion experiencing different local site symmetries in several wide-band-gap oxides, and then evaluate crystal field splittings of these Er3+ ions for their ground and excited states. The optical transitions between the ground state (Z) and excited state (Y) manifolds of the environmentally shielded 4f states of these Er3+ ions have wavelengths ~1.5 microns and thus have potential applications to quantum communications and quantum memories. These results are in excellent agreement with recent low-temperature measurements, provided the inadequate calculation of the 4f shell screening is adjusted by reducing the radial extent of the 4f wavefunctions by approximately a factor of 2.

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Yogendra Limbu, Yueguang Shi, Joseph Sink, Tharnier O. Puel, Durga Paudyal, Michael E. Flatté. 2025-01-06. Ab initio calculations of erbium crystal field splittings in oxide hosts. https://arxiv.org/abs/2501.03348

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