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Title: Optimization of the crystal growth of the superconductor CaKFe 4 As 4 from solution in the FeAs - CaFe 2 As 2 - KFe 2 As 2 system

Abstract

Measurements of the anisotropic properties of single crystals play a crucial role in probing the physics of new materials. Determining a growth protocol that yields suitable high-quality single crystals can be particularly challenging for multicomponent compounds. Here we present a case study of how we refined a procedure to grow single crystals of CaKFe 4As 4 from a high temperature, quaternary liquid solution rich in iron and arsenic (“FeAs self-flux”). Temperature dependent resistance and magnetization measurements are emphasized, in addition to the x-ray diffraction, to detect intergrown CaKFe 4As 4, CaFe 2As 2, and KFe 2As 2 within what appear to be single crystals. Guided by the rules of phase equilibria and these data, we adjusted growth parameters to suppress formation of the impurity phases. The resulting optimized procedure yielded phase-pure single crystals of CaKFe 4As 4. In conclusion, this optimization process offers insight into the growth of quaternary compounds and a glimpse of the four-component phase diagram in the pseudoternary FeAs–CaFe 2As 2–KFe 2As 2 system.

Authors:
 [1];  [2];  [1];  [1]
  1. Ames Lab. and Iowa State Univ., Ames, IA (United States)
  2. Ames Lab. and Iowa State Univ., Ames, IA (United States); Princeton Univ., Princeton, NJ (United States)
Publication Date:
Research Org.:
Ames Laboratory (AMES), Ames, IA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1417372
Report Number(s):
IS-J-9525
Journal ID: ISSN 2475-9953; PRMHAR
Grant/Contract Number:
AC02-07CH11358; GBMF4411
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review Materials
Additional Journal Information:
Journal Volume: 1; Journal Issue: 1; Journal ID: ISSN 2475-9953
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats

Meier, W. R., Kong, T., Bud'ko, S. L., and Canfield, P. C. Optimization of the crystal growth of the superconductor CaKFe4As4 from solution in the FeAs-CaFe2As2-KFe2As2 system. United States: N. p., 2017. Web. doi:10.1103/PhysRevMaterials.1.013401.
Meier, W. R., Kong, T., Bud'ko, S. L., & Canfield, P. C. Optimization of the crystal growth of the superconductor CaKFe4As4 from solution in the FeAs-CaFe2As2-KFe2As2 system. United States. doi:10.1103/PhysRevMaterials.1.013401.
Meier, W. R., Kong, T., Bud'ko, S. L., and Canfield, P. C. 2017. "Optimization of the crystal growth of the superconductor CaKFe4As4 from solution in the FeAs-CaFe2As2-KFe2As2 system". United States. doi:10.1103/PhysRevMaterials.1.013401.
@article{osti_1417372,
title = {Optimization of the crystal growth of the superconductor CaKFe4As4 from solution in the FeAs-CaFe2As2-KFe2As2 system},
author = {Meier, W. R. and Kong, T. and Bud'ko, S. L. and Canfield, P. C.},
abstractNote = {Measurements of the anisotropic properties of single crystals play a crucial role in probing the physics of new materials. Determining a growth protocol that yields suitable high-quality single crystals can be particularly challenging for multicomponent compounds. Here we present a case study of how we refined a procedure to grow single crystals of CaKFe4As4 from a high temperature, quaternary liquid solution rich in iron and arsenic (“FeAs self-flux”). Temperature dependent resistance and magnetization measurements are emphasized, in addition to the x-ray diffraction, to detect intergrown CaKFe4As4, CaFe2As2, and KFe2As2 within what appear to be single crystals. Guided by the rules of phase equilibria and these data, we adjusted growth parameters to suppress formation of the impurity phases. The resulting optimized procedure yielded phase-pure single crystals of CaKFe4As4. In conclusion, this optimization process offers insight into the growth of quaternary compounds and a glimpse of the four-component phase diagram in the pseudoternary FeAs–CaFe2As2–KFe2As2 system.},
doi = {10.1103/PhysRevMaterials.1.013401},
journal = {Physical Review Materials},
number = 1,
volume = 1,
place = {United States},
year = 2017,
month = 6
}

Journal Article:
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