High-Resolution Thermal Expansion of MgB2

R. Lortz; C. Meingast; D. Ernst; B. Renker; D. D. Lawrie; J. P. Franck

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High-Resolution Thermal Expansion of MgB2

R. Lortz·C. Meingast·D. Ernst·B. Renker·D. D. Lawrie·J. P. Franck

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Abstract

The thermal expansion of polycrystalline MgB2 from 5-300 K is studied using high-resolution capacitance dilatometry. The thermal expansivity exhibits a small jump of -5.8x10-8 K-1 at Tc (in accord with expectations from the Ehrenfest relationship and published specific heat and pressure data) and a negative peak-like feature close to 5 K. No indications of any structural instabilities are observed.

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R. Lortz, C. Meingast, D. Ernst, B. Renker, D. D. Lawrie, J. P. Franck. 2003-07-08. High-Resolution Thermal Expansion of MgB2. https://arxiv.org/abs/cond-mat/0307157

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