Growth, structure refinement, thermal expansion and optical spectroscopy of Tm3+-doped MgMoO4

• Published in: Optical materials Vol. 138; p. 113648
• Main Authors: Subbotin, Kirill, Titov, Anatolii, Lis, Denis, Zimina, Yulia, Didenko, Yana, Elabedine, Ghassen Zin, Eremeev, Kirill, Solé, Rosa Maria, Aguiló, Magdalena, Volkov, Pavel, Popov, Pavel, Chernova, Elena, Díaz, Francesc, Camy, Patrice, Loiko, Pavel, Mateos, Xavier
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.2023; Elsevier
• Subjects: Crystal structure; Czochralski method; Luminescence; Molybdates; Physics; Raman spectra; Thulium ions; Raman spectra; Czochralski method; Molybdates; Thulium ions; Luminescence; Crystal structure
• ISSN: 0925-3467; 1873-1252
• DOI: 10.1016/j.optmat.2023.113648

Thulium-doped magnesium molybdate single-crystal (Tm3+:MgMoO4) was grown by the Czochralski method (melting point: 1322 °C). The actual Tm3+ doping level was measured to be 0.1 at.% (the segregation coefficient was only 0.02). Tm:MgMoO4 belongs to the monoclinic class (sp. gr. C2/m, lattice constants: a = 10.2769(2) Å, b = 9.2898(5) Å, c = 7.0269(4) Å, β = 106.898(6)°). The thermal expansion tensor of this crystal is determined. Its thermal conductivity is also measured at 50–300 K (at room temperature, it amounts to 2.64 Wm−1K−1). Polarized Raman spectra are presented and the strongest mode is found at 957 cm−1. Optical spectroscopy of Tm3+ ions is studied indicating broad emission bands extending beyond 2 μm (the 3F4 → 3H6 transition) and a long lifetime of the 3F4 excited-state (1.972 ms). This makes Tm:MgMoO4 promising for broadly tunable and mode-locked lasers, when the technological problem of fabricating crystals with higher Tm3+ concentrations will be solved. •Czochralski growth of monoclinic thulium-doped magnesium molybdate - Tm3+:MgMoO4.•Rietveld refinement of the crystal structure, thermal exposition tensor determination.•Thermal conductivity is measured at 50–300 K, it is 2.64 Wm−1K−1 at room temperature.•Raman spectra are strongly polarized with the dominant mode at 957 cm−1.•Tm3+ ions exhibit broad emission extending beyond 2 μm and a long 3F4 lifetime.