Accession Number:

AD0672773

Title:

THERMAL CONDUCTIVITY AND ELECTRICAL RESISTIVITY MEASUREMENTS OF EUO ACROSS THE CURIE TEMPERATURE IN A MAGNETIC FIELD.

Descriptive Note:

Technical rept.,

Corporate Author:

SOUTH DAKOTA SCHOOL OF MINES AND TECHNOLOGY RAPID CITY DEPT OF PHYSICS

Personal Author(s):

• Konantz,Mark L.

Report Date:

1968-07-01

Pagination or Media Count:

65.0

Abstract:

The thermal conductivity K of a hot-pressed sample of EuO 90 EuO, 10 Eu2O3 was measured in the temperature range 60-300K using the linear absolute method. K falls off sharply as the temperature goes below 90K, and then rises again by 60K. The dip is not symmetric but its sides intersect at 69K. K was also measured in a longitudinal magnetic field of 100 gauss in the temperature range 60-78K. A dip at 69K was again observed however, in the magnetic field K fell off less sharply and the dip was much shallower. The electrical resistivity r was also measured. In the absence of the magnetic field r deviated by less than 1 from a value of 0.040 ohm-cm over the entire temperature range 60-300K. Application of the magnetic field resulted in changes of r of less than 2 throughout this same temperature range. The downward dip in the thermal conductivity at the ferromagnetic-paramagnetic transition temperature of 69K can be qualitatively understood in terms of critical scattering of phonons by critical fluctuation in the energy density of the spin system. Author

Descriptors:

• (*FERROMAGNETIC MATERIALS
• RARE EARTH ELEMENTS)
• (*RARE EARTH ELEMENTS
• TRANSPORT PROPERTIES)
• (*EUROPIUM COMPOUNDS
• TRANSPORT PROPERTIES)
• THERMAL CONDUCTIVITY
• ELECTRICAL RESISTANCE
• MAGNETIC FIELDS
• PHASE STUDIES
• TRANSITION TEMPERATURE
• CRYOGENICS
• NUCLEAR SPINS
• PHONONS
• INTERACTIONS
• THESES

Subject Categories:

• Electricity and Magnetism
• Solid State Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE