Abstract
Measurements of the nuclear-spin-lattice relaxation time and Hall effect in crystalline CdO, a degenerate semiconductor, have yielded the contact hyperfine strength of the conduction electrons at the nuclei. The product sec °K, independent of temperature and frequency for °K, and for MHz. Taking the carrier concentration independent of temperature to within 3% at 4.2, 77, and 300°K, and using an effective electron mass , we calculate an averaged electron probability density at the nucleus, , normalized to unity in an atomic volume. A comparison with in an isolated atom is interpreted to show that the Fermi level of the impurity band lies in the host-lattice conduction band. The Hall-effect data support this. The resonance frequency shift predicted from the Korringa relationship, -0.017%, is smaller than the observed shift, -0.031%. This is thought to be due to covalency contributions rather than to electron-electron interactions.
- Received 17 March 1969
DOI:https://doi.org/10.1103/PhysRev.184.705
©1969 American Physical Society