Synthesis and spectroscopy of Tm,Ho-codoped Y$_{2}$O$_{3}$ transparent ceramics for $2$-$\mu$m lasers
Roman N. Maksimova,
Vladislav A. Shitova,
Vladimir V. Osipova,
Albert N. Orlova,
Ekaterina M. Buzaevab,
Polina A. Ryabochkinab,
Aleksandr O. Ariskinb a Institute of Electrophysics UrB RAS, Ekaterinburg, Russian Federation
b National Research Mordovia State University, Saransk, Russian Federation
Abstract:
In this study, thulium and holmium codoped yttrium sesquioxide (Tm,Ho:Y
$_{2}$O
$_{3}$) transparent ceramics were fabricated using solid-state vacuum sintering of nano-sized particles with complex chemical composition synthesized by the laser ablation method. The as-produced powder was in the form of soft aggregates composing of individual spherical particles with a diameter of
$16$ nm, whose crystal structure underwent conversion from the monoclinic (space group C2/m) to the cubic (space group Ia-3) modification after consolidation into ceramic material. The morphological properties along with their correlation to the optical quality of Tm,Ho:Y
$_{2}$O
$_{3}$ ceramics vacuum sintered at
$1700$–-
$1775^\circ$ C were investigated. The sample sintered at
$1750^\circ$ C featured higher transmittances (
$81.6\%$ at
$\lambda=600$ nm and
$83.0\%$ at
$\lambda=1000$ nm) and lower content of scattering centers of
$0.00014$ vol.
$\%$. The absorption cross-section at
$797$ nm due to the
$^{3}$H
$_{6}\rightarrow{}^{3}$H
$_{4}$ transition of Tm
$^{3+}$ ions was
$4.44\times10^{-21}$ cm
$^{2}$. The broad luminescence band was observed from
$1750$ nm to
$2100$ nm owing to the combination of cross-relaxation of Tm
$^{3+}$ ions and nonradiative energy transfer from the
$^{3}$F
$_{4}$ level (Tm
$^{3+}$) to the
$^{5}$I
$_{7}$ level (Ho
$^{3+}$). These results suggest that Tm,Ho-codoped Y
$_{2}$O
$_{3}$ transparent ceramics are promising gain media for broadly tunable and mode-locked lasers emitting in the
$2$-
$\mu$m spectral range.
Keywords:
nanopowder, yttrium sesquioxide, optical ceramic, microstructure, codoping, nonradiative energy transfer.
UDC:
538.9: 535.37
Received: 02.11.2024
Received in revised form: 13.12.2024
Accepted: 24.03.2025
Language: English
Fulltext:
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