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arXiv · 2109.05780

Design rule for the emission linewidth of Eu$^{2+}$-activated phosphors

Yongchao Jia·Samuel Poncé·Anna Miglio·Masayoshi Mikami·Xavier Gonze
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Abstract

We study from first principles the emission linewidth of Eu$^{2+}$-doped LED phosphors. Based on the one-dimensional configuration coordinate model, an analysis of first principles data obtained for fifteen compounds show that, at working temperature, the linewidth of Eu$^{2+}$ emission band in solids is negligibly affected by quantum effects, and can be extracted from the Franck-Condon energy shifts. For a fixed Stokes shift, the difference of Franck-Condon energy shifts in the excited and ground states is the key factor for the FWHM determination. Narrow emission Eu$^{2+}$-doped LED phosphors are expected for the case with large positive value of such difference.

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Yongchao Jia, Samuel Poncé, Anna Miglio, Masayoshi Mikami, Xavier Gonze. 2021-09-13. Design rule for the emission linewidth of Eu$^{2+}$-activated phosphors. https://doi.org/10.1016/j.jlumin.2020.117258

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