Pressure dependence of the thermal and electrical conductivities of the intermetallic compounds AuCu and AuCu3

• The thermal diffusivity, a, electrical resistivity, ρ, and Seebeck coefficient, S, of ordered and disordered AuCu3 and AuCu have been measured as functions of T and P in the range 100–300 K and 0–2 GPa, and the thermal conductivity, λ, has been calculated from the data for a. The experimental data for ρ agree well with literature data. The ρ dependence of ρ and λ differs significantly between ordered and disordered specimens, but apart from the effect of impurity scattering the disordered materials behave much like the noble metals. For the temperature-dependent part of p (and λ) the P dependence differs by a factor of 2–3 between ordered and disordered states. This is shown to result from the difference in electron band structure, as reflected also in the thermoelectric parameter ξ. The P dependence of the relatively large lattice thermal conductivity of these materials causes the Lorenz ratio L = λρ/T to increase with ρ in all cases.

Subject headings

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Keyword

Thermal diffusivity

thermal conductivity

high pressure

electrical resistivity

Lorenz function

intermetallic compounds

alloys

gold-copper

copper-gold

AuCu

AuCu3

structural order

disorder

Seebeck coefficient

thermoelectric power

thermopower

lattice thermal conductivity

Condensed matter physics

Kondenserade materiens fysik

fysik

Physics

Publication and Content Type

ref (subject category)

art (subject category)