Luminescence Spectroscopy of Solids
There is an ongoing effort, in collaboration with a group at Boston College, to investigate the luminescent properties of solid-state laser materials, particularly rare earth ion- and transition metal ion-doped insulators. These materials are used for several applications, including lamp phosphors, lasers, display screens (for televisions, computers, etc.), and scintillators (for medical imaging). These materials are useful because, after absorbing energy, they emit light that is characteristic of the atoms that make up the solid. We investigate the processes that take place following the absorption energy. These processes include radiative decay (the emission of light), non-radiative decay (the conversion of energy into heat), and how energy is transferred among the ions in the solid.
Currently our efforts are focused in the following areas:
- The properties of oxides materials with metal-metal charge transfer states for potential application in solid state lighting devices
- An investigation into rare-earth ion doped phosphors for use in medical imaging systems
- Luminescent properties of nanoparticles doped with rare earth and transition metal ions, particularly on the role of surface states and on confinement effects.
- Upconversion processes as a tool in site-selective spectroscopy.
- Downconversion as method for increasing the efficiency of solar cells.
In recent years, I have had the pleasure of participating in schools and workshops at the International School of Atomic and Molecular Spectroscopy, which meet in Erice, Sicily during the summers. The topics cover the physics of optical materials, with the most recent workshop (2012) on "New Developments in Inorganic Luminescent Materials. Learn more about the Erice summer schools.
Recent and Current Support
This work is supported by the National Science Foundation under the following grants:
- National Science Foundation: Award 1126337, MRI: Acquisition of a pulsed laser/detection system for time-resolved studies of molecular complexes
- National Science Foundation: Award 1105907, RUI: Investigation of metal-to-metal charge transfer states in rare earth ion-doped solids (Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.)
- OSRAM Sylvania Corp.
- General Electric Corp.