Second-order structural transition in the superconductor La3Co4Sn13

Article

关键词: HEAVY-FERMION COMPOUNDS;    AUGMENTED-WAVE METHOD;    CRYSTAL-GROWTH;    METALS;    1ST-PRINCIPLES;    CA3IR4SN13;    STANNIDES;    TRANSPORT;    STATE;   

DOI  :  10.1103/PhysRevB.93.241112

来源: SCIE

【 摘 要 】

The quasiskutterudite superconductor La3Co4Sn13 undergoes a phase transition at T* = 152 K. By measuring the temperature dependence of heat capacity, electrical resistivity, and the superlattice reflection intensity using x rays, we explore the character of the phase transition at T*. Our lattice dynamic calculations found imaginary phonon frequencies around the M point when the high-temperature structure is used in the calculations, indicating that the structure is unstable at the zero-temperature limit. The combined experimental and computational results establish that T* is associated with a second-order structural transition with q = (0.5,0.5,0) (or the M point). Further electronic band structure calculations reveal Fermi surface sheets with low-curvature segments, which allow us to draw qualitative comparison with both Sr3Ir4Sn13 and Sr3Rh4Sn13 in which similar physics has been discussed recently.

【 授权许可】

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