Single Crystal Growth and Characterization of the Iron-Based Superconductor KFe₂As₂Synthesized by KAs Flux Method

Abstract

Centimeter sized platelet single crystals of KFe2As2 were grown using a self-flux method. An encapsulation technique using commercial stainless steel container allowed the stable crystal growth lasting for more than 2 weeks. Ternary K-Fe-As systems with various starting compositions were examined to determine the optimal growth conditions. Employment of KAs flux led to the growth of large single crystals with the typical size of as large as 15 mm × 10 mm × 0.4 mm. The grown crystals exhibit sharp superconducting transition at 3.4 K with the transition width 0.2 K, as well as the very large residual resistivity ratio exceeding 450, evidencing the good sample quality.

Potential Antiferromagnetic Fluctuations in Hole-Doped Iron-Pnictide Superconductor Ba1-xKxFe2As2 Studied by 75As Nuclear Magnetic Resonance Measurement

“…The detailed procedure of single crystal growth is basically the same described in ref. 39 which reports the single crystal growth of an end member of the system, KFe 2 As 2 . The ratio of Ba and K was determined by the energy dispersive X-ray spectroscopy.…”

Comprehensive scenario for single-crystal growth and doping dependence of resistivity and anisotropic upper critical fields in (Ba1−xKx)FeLiu1, Tanatar2, Straszheim3 et al. 2014Phys. Rev. B6215722View full textAdd to dashboardCite

“…Studies were performed in the underdoped, x < 0.4 [29,30] compositions, for which high-quality single crystals can be grown from FeAs flux [31], or in heavily overdoped range x > 0.76 [32], where crystals were prepared from KAs flux [33]. Crystals of BaK122 can be also grown from Sn flux [34], however, their properties are notably affected by Sn inclusions at sub-percent level and will not be discussed here.…”

Magnetic Penetration Depth in the FeAs-Based Superconductor KFe2As2

“…High-quality single-crystalline samples of KFe 2 As 2 were grown by a self-flux method which will be described in detail elsewhere [12]. From the temperature dependence of susceptibility,the T c was estimated to be 3.5 K. The µSR measurements were conducted at both the M15 beamline at TRI-UMF, Vancouver, Canada and at the RIKEN-RAL Muon Facility at Ruthreford Appleton Laboratory, Didcot, UK.…”