Absence of a structural transition up to 40 GPa inMgB2and the relevance of magnesium nonstoichiometry

2001/06/28 by P. Bordet, Mohamed Mézouar, M. Mezouar +13 · 2 citations
Materials Science · Physics and Astronomy · #Magnetic Properties of Alloys #Physics of Superconductivity and Magnetism #Superconductivity in MgB2 and Alloys #cond-mat.mtrl-sci #cond-mat.supr-con

paper · pdf · doi:10.1103/physrevb.64.172502

submitted March 9th 2001, PRB accepted

arxiv created 2001/06/28 · openalex publication_date 2001/10/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28

Abstract

We report measurements on MgB₂ up to \ensuremath∼40 GPa. Increasing pressure yields a monotonous decrease of the lattice parameters and of the c/a ratio, but no structural transition down to parameters smaller than those of AlB₂. The transition superconducting temperature also decreases with temperature in a sample-dependent way. The results are explained by an increase of the filling of the two-dimensional p_xy bands with pressure, the Mg stoichiometry determining the starting position of the Fermi level. Our measurements indicate that these hole bands are the relevant ones for superconductivity.

Citations

• Recent advances in magnetic structure determination by neutron powder diffraction

Cited by

• Dependence of the superconducting transition temperature of single and polycrystalline MgB2 on hydrostatic pressure
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