1 M ay 2 00 1 The Dependence of T c on Hydrostatic Pressure in Superconducting MgB
نویسنده
چکیده
The dependence of Tc on hydrostatic (He-gas) pressure for superconducting MgB2 has been determined to 0.7 GPa. We find that Tc decreases linearly and reversibly under pressure at the rate dTc/dP ≃ −1.11 ± 0.02 K/GPa. These studies were carried out on the same sample used in earlier structural studies under He-gas pressure which yielded the bulk modulus B = 147.2± 0.7 GPa. The value of the logarithmic volume derivative of Tc is thus accurately determined, d lnTc/d ln V = +4.16 ± 0.08, allowing quantitative comparison with theory. The present results support the emerging picture that MgB2 is a BCS superconductor with electron-phonon pairing interaction.
منابع مشابه
The Dependence of T c on Hydrostatic Pressure in Superconducting MgB
The dependence of Tc on pure hydrostatic pressure has been determined for the first time on the recently discovered superconductor MgB2 . Using a He-gas apparatus, we find that Tc decreases under pressure to 0.5 GPa at a significantly smaller rate, dTc/dP ≃ −1.11± 0.02 K/GPa, than found in other studies under less hydrostatic pressure conditions. The value of the logarithmic volume derivative, ...
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