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Title: Anisotropic upper critical fields up to 63 T in CaKFe 4As 4 single crystals

Abstract

The discovery of Fe-based superconductors (FBS) has intensified research on mechanisms of hightemperature superconductivity as well as searches for materials with higher superconducting transition temperatures, Tc. Among many different classes of FBS, the so called “122” family is one of the most well studied systems. However, superconductivity in “122” systems is often stabilized via chemical substitution, which inevitably invites chemical disorder. Recently, a new compound, CaKFe 4As 4, with a well ordered structure that is essentially composed of alternating “122” layers, was discovered with a T c of 35 K. We were able to perform the first single crystal study and measured the anisotropic upper critical fields, H c2, up to 63 T.

Authors:
 [1];  [2];  [1];  [3];  [1];  [1]
  1. Ames Lab., Ames, IA (United States)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  3. Old Dominion Univ., Norfolk, VA (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1343722
Report Number(s):
LA-UR-17-21118
DOE Contract Number:
AC52-06NA25396
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; High Magnetic Field Science

Citation Formats

Kong, T., Balakirev, Fedor Fedorovich, Meier, W. R., Gurevich, A., Canfield, P. C., and Bud'ko, S. L.. Anisotropic upper critical fields up to 63 T in CaKFe4As4 single crystals. United States: N. p., 2017. Web. doi:10.2172/1343722.
Kong, T., Balakirev, Fedor Fedorovich, Meier, W. R., Gurevich, A., Canfield, P. C., & Bud'ko, S. L.. Anisotropic upper critical fields up to 63 T in CaKFe4As4 single crystals. United States. doi:10.2172/1343722.
Kong, T., Balakirev, Fedor Fedorovich, Meier, W. R., Gurevich, A., Canfield, P. C., and Bud'ko, S. L.. Mon . "Anisotropic upper critical fields up to 63 T in CaKFe4As4 single crystals". United States. doi:10.2172/1343722. https://www.osti.gov/servlets/purl/1343722.
@article{osti_1343722,
title = {Anisotropic upper critical fields up to 63 T in CaKFe4As4 single crystals},
author = {Kong, T. and Balakirev, Fedor Fedorovich and Meier, W. R. and Gurevich, A. and Canfield, P. C. and Bud'ko, S. L.},
abstractNote = {The discovery of Fe-based superconductors (FBS) has intensified research on mechanisms of hightemperature superconductivity as well as searches for materials with higher superconducting transition temperatures, Tc. Among many different classes of FBS, the so called “122” family is one of the most well studied systems. However, superconductivity in “122” systems is often stabilized via chemical substitution, which inevitably invites chemical disorder. Recently, a new compound, CaKFe4As4, with a well ordered structure that is essentially composed of alternating “122” layers, was discovered with a Tc of 35 K. We were able to perform the first single crystal study and measured the anisotropic upper critical fields, Hc2, up to 63 T.},
doi = {10.2172/1343722},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Feb 13 00:00:00 EST 2017},
month = {Mon Feb 13 00:00:00 EST 2017}
}

Technical Report:

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