Thermal and electrical transport measurements in single crystal beryllium at low temperatures

Thesis/Dissertation · Sat Jan 01 00:00:00 EST 1977

OSTI ID:6306902

Nelson, W E

Experimental results for the thermal conductivity and electricity resistivity of a beryllium single crystal (RRR - 1750) are presented for 3K<35K in a longitudinal magnetic field up to 70KG. Residual resistivity at 4K was 1.86 nano-ohm-cm, and a thermal conductivity maximum of 140 watts/cmK was observed at 13.8K. Wiedemann-Franz-Lorenz behavior is given from 2.5K to 30K, and evidences a residual plateau value of 2.1 x 10/sup -8/V/sup 2/K/sup 2/. Electrical resistivity data has been fit using a Matthiessen type expression containing a residual and a temperature dependent term. A T/sup 3/ Debye temperature dependence is observed below 35K and deviations from Matthiessen's rule are concluded to be negligible. Thermal conductivity data has been fit to a standard STM expression containing a residual term in T/sup -1/ as well as an intrinsic term in T/sup n/, where n approx. equals 2, and deviations are observed. Thermal and electrical transport properties were also measured for OFHC copper over the same range of temperature and magnetic field to verify experimental techniques used in the beryllium experiments. These results are the first to provide confirmation of the Sommerfield value of the Wiedemann-Franz-Lorenz ratio in the residual plateau region for copper of this purity.

• Research Organization: Massachusetts Univ., Amherst (USA)
• OSTI ID: 6306902
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BERYLLIUM
ELECTRIC CONDUCTIVITY
THERMAL CONDUCTIVITY
COPPER
EXPERIMENTAL DATA
MONOCRYSTALS
TEMPERATURE DEPENDENCE
WIEDEMANN-FRANZ LAW
ALKALINE EARTH METALS
CRYSTALS
DATA
ELECTRICAL PROPERTIES
ELEMENTS
INFORMATION
METALS
NUMERICAL DATA
PHYSICAL PROPERTIES
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENTS
360104* - Metals &amp; Alloys- Physical Properties
656102 - Solid State Physics- Superconductivity- Acoustic
Electronic
Magnetic
Optical
&amp; Thermal Phenomena- (-1987)