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arXiv · 0905.0968

Intrinsic Properties of AFe2As2 (A = Ba, Sr) Single Crystal under Highly Hydrostatic Pressure Conditions

Kazuyuki Matsubayashi·Naoyuki Katayama·Kenya Ohgushi·Atsushi Yamada·Kouji Munakata·Takehiko Matsumoto·Yoshiya Uwatoko
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Abstract

We measured the electrical resistivity and ac magnetic susceptibility of BaFe2As2 and SrFe2As2 single crystals under pressure using a cubic anvil apparatus. For BaFe2As2, the antiferromagnetic (AF) and structural transitions are suppressed with increasing pressure. Unexpectedly, these transitions persist up to 8 GPa, and no signature of a superconducting transition was observed in the pressure range investigated here. On the other hand, the AF and structural transitions of SrFe2As2 collapse at around the critical pressure Pc ~ 5 GPa, resulting in the appearance of bulk superconductivity. The superconducting volume fraction abruptly increases above Pc, and shows a dome centered at approximately 6 GPa. Our results suggest that the bulk superconducting phase competes with the AF/orthorhombic phase and only appears in the narrow pressure region of the tetragonal phase.

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Kazuyuki Matsubayashi, Naoyuki Katayama, Kenya Ohgushi, Atsushi Yamada, Kouji Munakata, Takehiko Matsumoto, Yoshiya Uwatoko. 2009-06-05. Intrinsic Properties of AFe2As2 (A = Ba, Sr) Single Crystal under Highly Hydrostatic Pressure Conditions. https://doi.org/10.1143/jpsj.78.073706

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