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Robust zero resistance in a superconducting high-entropy alloy at pressures up to 190 GPa

  1. Liling Suna,b,e,2
  1. aInstitute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
  2. bDepartment of Physics, University of Chinese Academy of Sciences, Beijing 100190, China;
  3. cDepartment of Chemistry, Princeton University, Princeton, NJ 08544;
  4. dShanghai Synchrotron Radiation Facilities, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, China;
  5. eCollaborative Innovation Center of Quantum Matter, Beijing, 100190, China
  1. Contributed by Robert J. Cava, November 1, 2017 (sent for review September 27, 2017; reviewed by M. Brian Maple and Maw-Kuen Wu)

Significance

High-entropy alloys (HEAs) are made from multiple transition-metal elements in equimolar or near-equimolar ratios. The elements in HEAs arrange themselves randomly on the crystallographic positions of a simple lattice. In addition to their excellent mechanical properties, one HEA has been reported to display superconductivity. In this work, we report that the Ta–Nb–Hf–Zr–Ti high-entropy alloy superconductor exhibits extraordinarily robust zero-resistance superconductivity under pressure up to 190.6 GPa. This is an observation of the zero-resistance state of a superconductor all the way from 1-bar pressure to the pressure of the earth’s outer core without structure phase transition, making the superconducting HEA a promising candidate for new application under extreme condition.

Abstract

We report the observation of extraordinarily robust zero-resistance superconductivity in the pressurized (TaNb)0.67(HfZrTi)0.33 high-entropy alloy––a material with a body-centered-cubic crystal structure made from five randomly distributed transition-metal elements. The transition to superconductivity (TC) increases from an initial temperature of 7.7 K at ambient pressure to 10 K at ~60 GPa, and then slowly decreases to 9 K by 190.6 GPa, a pressure that falls within that of the outer core of the earth. We infer that the continuous existence of the zero-resistance superconductivity from 1 atm up to such a high pressure requires a special combination of electronic and mechanical characteristics. This high-entropy alloy superconductor thus may have a bright future for applications under extreme conditions, and also poses a challenge for understanding the underlying quantum physics.

Footnotes

  • ?1J.G., H.W., and F.v.R. contributed equally to this work.

  • ?2To whom correspondence may be addressed. Email: rcava{at}princeton.edu or llsun{at}iphy.ac.cn.
  • Author contributions: R.J.C. and L.S. designed research; J.G., H.W., F.v.R., Z.W., S.C., Y.Z., K.Y., A.L., S.J., and L.S. performed research; J.G., H.W., F.v.R., Z.W., S.C., Y.Z., K.Y., A.L., S.J., Q.W., R.J.C., and L.S. analyzed data; and J.G., Q.W., R.J.C., and L.S. wrote the paper.

  • Reviewers: M.B.M., University of California, San Diego; and M.-K.W., Academia Sinica.

  • The authors declare no conflict of interest.

  • This article contains supporting information online at www.danielhellerman.com/lookup/suppl/doi:10.1073/pnas.1716981114/-/DCSupplemental.

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