Composition-tuning in a solid-state electrotransport furnace with active thermal expansion compensation

A new solid-state electrotransport (SSE) apparatus for refining ultra-puresingle crystals of metallic compounds under ultra-high vacuum is described. The setup employs a novelthermal expansion compensation mechanism to minimize mechanical stress on the sample during refinement with cold clamps for contamination-less purification at elevated temperatures. The apparatus is designed to tune the composition of initially slightly off-stoichiometric samples. Theexpansion compensation and stress-free operation were tested by recording thethermal expansion of elemental cerium in a treatment up to 655  °C. SSE refinement was then performed on a high-qualitysingle crystal of U6Fe resulting in a 50% increase of its residualresistivity ratio to the highest value obtained for asingle crystal to date.

Source: Review of Scientific Instruments - December 8, 2016 Category: Physics Authors: J. L. Schmehr, W. Whitley and A. D. Huxley Source Type: research