1Institute of Materials Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan2Department of Physics, Bahauddin Zakariya University, Multan 60800, Pakistan3Advanced Materials Laboratory, National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan4Japan Aerospace Exploration Agency, ISS Science Project Office, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan
Optical Transmittance and Band Gap of Ferroelectric BaTi2O5 Bulk Glass
1Institute of Materials Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan2Department of Physics, Bahauddin Zakariya University, Multan 60800, Pakistan3Advanced Materials Laboratory, National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan4Japan Aerospace Exploration Agency, ISS Science Project Office, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan
Optical transmittance and reflectance on ferroelectric BaTi2O5 glasses prepared recently by a containerless synthesis technique are measured at room temperature in the wavelength range 190-800nm. The fundamental absorption edge located around 340nm demonstrates the colourless and transparent character of the glass. The optical band gap of 3.32eV has been estimated. The tail of the optical absorption near the fundamental absorption edge is found to follow the Urbach rule. Our analysis of the experimental spectra supports an indirect allowed interband transition between the valence band formed by O-2p orbitals and the conduction band formed by Ti-3d orbitals.
Optical transmittance and reflectance on ferroelectric BaTi2O5 glasses prepared recently by a containerless synthesis technique are measured at room temperature in the wavelength range 190-800nm. The fundamental absorption edge located around 340nm demonstrates the colourless and transparent character of the glass. The optical band gap of 3.32eV has been estimated. The tail of the optical absorption near the fundamental absorption edge is found to follow the Urbach rule. Our analysis of the experimental spectra supports an indirect allowed interband transition between the valence band formed by O-2p orbitals and the conduction band formed by Ti-3d orbitals.
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2008, Vol. 25 
