STUDY OF CESIUM ON REFRACTORY METALS USING FIELD EMISSION MICROSCOPY.
Abstract
The document is a study of the cause of the cyclic and spontaneous migrations of cesium on refractory metals. Data supporting the hypothesis that the spontaneous migration is the result of lattice heating by emission of electrons of less than Fermi energy have been obtained. Calculations of the activation energy for cesium migration on a cesium substrate using these data are in agreement with results of other workers. The spontaneous migration was very similar for different emitter types and appeared to be almost the same for all substrates. Variations in rates of migration were dependent upon applied field, but not on environmental pressure or temperature. A mechanism has been proposed for the cyclic migration. The mechanism presupposes a critical temperature above which the lattice is cooled by emission. Oscillation about this temperature, coupled with cesium adsorption and migration, appear to be important. The interpretation agrees with experimental results, since it predicts that the effect will be nearly the same for all refractory metal substrates. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1964
- Accession Number
- AD0603902
Entities
People
- James L. Gumnick
Organizations
- Glenn L. Martin Company