Characterization of special glasses and crystals doped with transition ions using thermal lens, optical beam deflection and photoacoustic techniques

• Grant number: 06/02514-8
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2006
• End date: July 31, 2008
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Antonio Manoel Mansanares
• Grantee: Antonio Manoel Mansanares
• Host Institution: Instituto de Física Gleb Wataghin (IFGW). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Thermal Lens and Optical Beam Deflection techniques, besides Photoacoustics, will be employed in the study of borosilicate glasses doped with semiconductors and treated at several temperatures to obtain nanocrystals (quantum dots), and also in the investigation of A2BMF6 crystals doped with transition ions. In the first case, the size distribution of the quantum dots depends on the temperature and treatment time. Photothermal techniques will be used in the determination of the absorption spectra as a function of the annealing conditions, as well as in the investigation of the thermal and optothermal properties (thermal diffusivity, dn/dT). In the second case, the substitution of crystal atoms by the transition ions will be investigated through optical absorption spectra (photoacoustics) and electron paramagnetic resonance (crystal field distortions). Besides, using Thermal Lens and Photoacoustics it is possible to determine the thermal parameters (diffusivity and conductivity) and dn/dT, which are anisotropic (hexagonal lattice) and are dependent on the lattice modifications introduced by the ions. (AU)