Accession Number : AD0604089

Title :   DEPENDENCE OF SPIN-LATTICE RELAXATION TIME UPON MAGNETIC FIELD FOR TWO SALTS OF NEODYMIUM.

Descriptive Note : Technical rept. no. 15,

Corporate Author : CALIFORNIA UNIV BERKELEY

Personal Author(s) : Baker,J. M. ; Ford,N. C. ,Jr.

Report Date : AUG 1964

Pagination or Media Count : 43

Abstract : Measurements were made below 1.5K of the spin-lattice relaxation rate of Nd(3+) in lanthanum fluoride and lanthanum magnesium nitrate as a function of the separation of the levels of the ground doublet. The relaxation rate for the forbidden transition was calculated, and it has been shown that under certain circumstances it can be more rapid than the relaxation rate for allowed transitions. There is an additional tribution which depends upon the concentration of Nd(3+) and may be due to cross relaxation to coupled pairs of Nd(3+) ions. In lanthanum magnesium nitrate there is a phonon bottleneck as well as the direct process. Both salts show an Orbach process above 2K. A modification of the usual pulse saturation technique was used to obtain these measurements which gives some advantages over the standard method.

Descriptors :   (*NEODYMIUM, *RELAXATION TIME), (*CRYSTAL LATTICES, IMPURITIES), (*LANTHANUM COMPOUNDS, PARAMAGNETIC RESONANCE), FLUORIDES, NITRATES, MAGNESIUM COMPOUNDS, IONS, MICROWAVE SPECTROSCOPY, NUCLEAR SPINS, ELECTRON TRANSITIONS, SELECTION RULES(PHYSICS), PHONONS, PARAMAGNETIC MATERIALS, HYPERFINE STRUCTURE, MAGNETIC FIELDS

Subject Categories : Inorganic Chemistry
      Crystallography
      Nuclear Physics & Elementary Particle Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE