Mixed magnetic dipole and electric quadrupole hyperfine interactions studied by nuclear orientation with and without nuclear magnetic resonance

Abstract

This paper considers the effect on both conventional nuclear orientation, and on the combined nuclear magnetic resonance/nuclear orientation (NMR/ON) techniques, when a small electric quadrupole interaction is added to a simple magnetic nuclear hyperfine hamiltonian. It is shown that such an addition is difficult to detect by conventional nuclear orientation and can lead to substantial misinterpretation of experimental results. Quantitative examples are given. The effect of such an addition on the NMR/ON resonance line spectrum is discussed in detail and it is shown that, for the linewidths found in ferromagnetic metals, this combined technique can detect electric quadrupole couplings eQVzz of order 0.1% of the magnetic dipole coupling. A discussion of possible sources of such quadrupole interaction and dilute impurities in ferromagnetic metals is included.