Collapsed tetragonal phase transition in LaRu2P2

Article

关键词: HIGH-TEMPERATURE SUPERCONDUCTIVITY;    SINGLE-CRYSTALS;    SOLUTION GROWTH;    IRON;    PHOSPHIDES;   

DOI  :  10.1103/PhysRevB.96.184509

来源: SCIE

【 摘 要 】

The structural properties of LaRu2P2 under external pressure have been studied up to 14 GPa, employing high-energy x-ray diffraction in a diamond-anvil pressure cell. At ambient conditions, LaRu2P2 (I4/mmm) has a tetragonal structure with a bulk modulus of B = 105(2) GPa and exhibits superconductivity at T-c = 4.1 K. With the application of pressure, LaRu2P2 undergoes a phase transition to a collapsed tetragonal (cT) state with a bulk modulus of B = 175(5) GPa. At the transition, the c-lattice parameter exhibits a sharp decrease with a concurrent increase of the a-lattice parameter. The cT phase transition in LaRu2P2 is consistent with a second-order transition, and was found to be temperature dependent, increasing from P = 3.9(3) GPa at 160 K to P = 4.6(3) GPa at 300 K. In total, our data are consistent with the cT transition being near, but slightly above 2 GPa at 5 K where superconductivity is suppressed. Finally, we compare the effect of physical and chemical pressure in the RRu2P2 (R = Y, La-Er, Yb) isostructural series of compounds and find them to be analogous.

【 授权许可】

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