Spectroscopy of solid-solution transparent sesquioxide laser ceramic Tm:LuYO3

• Published in: Optical materials express Vol. 12; no. 9; p. 3749
• Main Authors: Eremeev, Kirill, Loiko, Pavel, Braud, Alain, Camy, Patrice, Zhang, Jian, Xu, Xiaodong, Zhao, Yongguang, Liu, Peng, Balabanov, Stanislav, Dunina, Elena, Kornienko, Alexey, Fomicheva, Liudmila, Mateos, Xavier, Griebner, Uwe, Petrov, Valentin, Wang, Li, Chen, Weidong
• Format: Journal Article
• Language: English
• Published: Washington Optical Society of America 01-09-2022; OSA pub
• Subjects: Argon; Ceramic powders; Ceramics; Hot isostatic pressing; Low temperature; Physics; Radiative lifetime; Sesquioxides; Solid solutions; Spectrum analysis; Yttrium oxide
• ISSN: 2159-3930; 2159-3930
• DOI: 10.1364/OME.471492

We report on a detailed spectroscopic study of a Tm3+-doped transparent sesquioxide ceramic based on a solid-solution (lutetia – yttria, LuYO3) composition. The ceramic was fabricated using commercial oxide powders by hot isostatic pressing at 1600°C for 3 h at 190 MPa argon pressure. The most intense Raman peak in Tm:LuYO3 at 385.4 cm-1 takes an intermediate position between those for the parent compounds and is notably broadened (linewidth: 12.8 cm-1). The transition intensities of Tm3+ ions were calculated using the Judd-Ofelt theory; the intensity parameters are O2 = 2.537, O4 = 1.156 and O6 = 0.939 [1020 cm2]. For the 3F4 → 3H6 transition, the stimulated-emission cross-section amounts to 0.27 × 10-20 cm2 at 2059nm and the reabsorption-free luminescence lifetime is 3.47 ms (the 3F4 radiative lifetime is 3.85 ± 0.1 ms). The Tm3+ ions in the ceramic exhibit long-wave multiphonon-assisted emission extending up to at least 2.35 µm; a phonon sideband at 2.23 µm is observed and explained by coupling between electronic transitions and the dominant Raman mode of the sesquioxides. Low temperature (12 K) spectroscopy reveals a significant inhomogeneous spectral broadening confirming formation of a substitutional solid-solution. The mixed ceramic is promising for ultrashort pulse generation at >2 µm.