Search for Far Infrared Radiation from Optically Pumped Defect Modes
Abstract
A comprehensive experimental study of the near millimeter wave dynamics of a variety of solids is being carried out. Since in many cases the investigation involves driving the system far from equilibrium with IR or UV laser radiation, knowledge of the time dependent optical response over a broad frequency region is required. Effects such as persistent IR spectral hole burning and population inversion in internal vibrational modes in solids have been uncovered using this approach. The discovery that persistent IR hole burning can be used to manipulate the near millimeter wave response of defects in crystals, such as NO2(-):KI, and that it also provides a sensitive probe of the optical photodarkening in chalcogenide glasses have opened up new research avenues which require simultaneous probes of very different frequencies in the IR and visible. On going exploration of the far IR response of high temperature superconductors in sintered, thin film, single crystal and even single grain form continue to provide new information about the dynamical response of these unusual materials both in the normal and superconducting states. (jhd)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 13, 1989
- Accession Number
- ADA216976
Entities
People
- A. J. Sievers
Organizations
- Cornell University