Spectroscopic properties of a Tm3+:Bi2TeO5 single crystal

• Published in: Crystal research and technology (1979) Vol. 42; no. 12; pp. 1335 - 1340
• Main Authors: Dominiak-Dzik, G., Ryba-Romanowski, W., Lisiecki, R., Főldvári, I.
• Format: Journal Article
• Language: English
• Published: Berlin WILEY-VCH Verlag 01.12.2007; WILEY‐VCH Verlag
• Subjects: absorption; bismuth tellurite crystal; lifetimes; luminescence; thulium ion
• ISSN: 0232-1300; 1521-4079
• DOI: 10.1002/crat.200711028

Single crystal of bismuth tellurite Bi2TeO5 (BTO) doped with trivalent thulium (Tm3+) was grown by the Czochralski method and investigated by spectroscopic techniques (absorption, emission). Absorption and emission of the Tm:BTO crystal collected in the VIS‐IR spectral range are presented. Spectroscopic features were investigated as a function of the excitation light polarisation (E//X, Y, and Z axis of optical indicatrix) and sample temperature. The oscillator strength of the 3H6 → 3F4 transition at 1.7 μm was determined by numerical integration of the X, Y and Z polarised absorption spectra. The obtained values are: PX = 4.7 × 10−6, PY = 6.8 × 10−6 and PZ = 5.9 × 10−6 that gives a mean value Pmean = 5.8 × 10−6. Emission was observed from the 1G4 and 3H4 levels. The 3H4 and 1G4 excited state dynamics was studied. Decay curves and time constants of luminescence were collected at 5 and 300 K and analysed. The 3F4 → 3H6 luminescence at around 1.8 μm was too weak to be acquired from the low concentrated sample. However, based on optical data it was possible to estimate the radiative probability Arad of this transition and the 3F4 radiative lifetime. The resultant values are: Arad = 668 ± 0.4 s−1 and τrad = 1.5 ms. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)