Publications Repository - Gdańsk University of Technology

Polycrystalline HfPd2Al has been synthesized using the arc-melting method and studied under ambient-pressure conditions by x-ray diffraction from room temperature up to 450 °C. High-pressure x-ray diffraction up to 23 GPa was also performed using Diacell-type membrane diamond anvil cells. The estimated linear thermal expansion coefficient was found to be α=1.40(3)×10−5K−1, and the bulk modulus derived from the fit to the third-order Birch-Murnaghan equation of state is B0=97(2) GPa. Resistivity studies under applied pressure (p≤7.49GPa) showed a linear decrease of superconducting critical temperature with increasing pressure and the slope dTc/dp=−0.13(1)KGPa−1. The same behavior is observed for the electron-phonon coupling constant λep(p) that changes from 0.67 to 0.6, estimated for p=0.05 and 7.49 GPa, respectively. First-principles electronic structure and phonon calculation results are presented and used to estimate the magnitude of electron-phonon interaction λep and its evolution with pressure. Theoretical results explain the experimentally observed decrease in Tc due to considerable lattice stiffening.

Authors

• B. Wiendlocha,
• Michał Winiarski link open in new tab ,
• M. Muras,
• C. Zvoriste-Walters,
• J. C. Griveau,
• S. Heathman,
• prof. dr hab. inż. Maria Gazda link open in new tab ,
• prof. dr hab. inż. Tomasz Klimczuk link open in new tab