Optical Hole Burning Studies in Glasses Doped with Dyes and Rare-Earth Ions

摘要

Rare-earth ion doped glasses and dye doped sol-gel glasses and spin- coated polymers were prepared and investigated by optical methods at room and liquid helium temperatures. Eu3+ glasses revealed large inhomogeneous broadenings (3-6 nm) and these samples also exhibited transient spectral hole burning at cryogenic temperatures. Hole burning studies in Eu3+ doped YSO and CaF2 revealed more than 40 sites for the dopants. These were due to clustering of the dopants and dopant induced microscopic defects. Infrared quantum counter studies were also performed on Eu3+ doped materials. Our studies revealed that Eu3+ doped materials are suitable for the development of room temperature photon detectors for infrared radiation using the two-photon absorption scheme. Spectroscopy of thulium doped chelates was performed. Broad spectral holes (180- 360 MHz)were burned in the 3H6 yields 3H4 transition, which lasted for 10 hours at 1.4K. Suitability of this material for frequency and time domain information storage is under investigation. The effect of mechanical vibrations of the closed cycle refrigeration system was also investigated by optical means. A rigidly held device was found to vibrate with an amplitude of 50 microns.