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arXiv · 1207.0919

Photoluminescence in electronic ferroelectric Er_{1-x}Yb_xFe_2O_4

R. Wang·H. X. Yang·Y. B. Qin·B. Dong·J. Q. Li·Jimin Zhao
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Abstract

Strong Stark splitting, which is nearly independent of the R-ions replacement, has been observed through the photoluminescence investigation of electronic ferroelectric Er1-xYbxFe2O4 (x=0, 0.8, 0.9 and 0.95). Initially multiple radiative decay channels have been investigated, especially the visible transition 4F9/2-->4I15/2, of which a quenching effect has been observed. A series of small non-Raman peaks have been observed superimposed on a broadband photoluminescence spectrum, of which we tentatively assign Stark splitting to be the cause. The splitting of the 4F9/2 and 4I15/2 levels is found to be 54meV and 66meV, respectively. This unusually large Stark splitting at visible range indicates the existence of strong local field originated from the W-layer in the charge-frustrated ErFe2O4.

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R. Wang, H. X. Yang, Y. B. Qin, B. Dong, J. Q. Li, Jimin Zhao. 2012-07-04. Photoluminescence in electronic ferroelectric Er_{1-x}Yb_xFe_2O_4. https://doi.org/10.1063/1.3490212

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