Pressure effects on the superconductivity of the HfPd2Al Heusler compound: Experimental and theoretical study

B. Wiendlocha; M. J. Winiarski; M. Muras; C. Zvoriste-Walters; J.-C. Griveau; S. Heathman; M. Gazda; T. Klimczuk

doi:10.1103/PhysRevB.91.024509

← Back to search

Pressure effects on the superconductivity of the HfPd2Al Heusler compound: Experimental and theoretical study

B. Wiendlocha, M. J. Winiarski, M. Muras, C. Zvoriste-Walters, J.-C. Griveau, S. Heathman, M. Gazda, T. Klimczuk

DOI 10.1103/PhysRevB.91.024509 · Physical Review B

T1

Active bibliographic source — not scientific approval

Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.

Abstract

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.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
HfPd2Al Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	3.53	Pressure unresolved	midpoint
HfPd2Al Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	3.55	Pressure unresolved	midpoint
HfPd2Al Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	3.7	Pressure not reported	unknown