Publisher's Note: High-temperature superconductivity stabilized by electron-hole interband coupling in collapsed tetragonal phase of ${\mathrm{KFe}}_2{\mathrm{As}}_2$ under high pressure [Phys. Rev. B 91 , 060508(R) (2015)]

Journal Article · Mon Mar 09 00:00:00 EDT 2015 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PhysRevB.91.099902· OSTI ID:1335147

Nakajima, Yasuyuki ^[1]; Wang, Renxiong ^[1]; Metz, Tristin ^[1]; Wang, Xiangfeng ^[1]; Wang, Limin ^[1]; Cynn, Hyunchae ^[1]; Weir, Samuel T. ^[1]; Jeffries, Jason R. ^[2]; Paglione, Johnpierre ^[1]

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1. Univ. of Maryland, College Park, MD (United States)
2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Here, we report a high-pressure study of simultaneous low-temperature electrical resistivity and Hall effect measurements on high quality single-crystalline KFe₂As₂ using designer diamond anvil cell techniques with applied pressures up to 33 GPa. In the low pressure regime, we show that the superconducting transition temperature T_c finds a maximum onset value of 7 K near 2 GPa, in contrast to previous reports that find a minimum T_c and reversal of pressure dependence at this pressure. Upon applying higher pressures, this T_c is diminished until a sudden drastic enhancement occurs coincident with a first-order structural phase transition into a collapsed tetragonal phase. The appearance of a distinct superconducting phase above 13 GPa is also accompanied by a sudden reversal of dominant charge carrier sign, from hole- to electron-like, which agrees with our band calculations predicting the emergence of an electron pocket and diminishment of hole pockets upon Fermi surface reconstruction. Our results suggest the high-temperature superconducting phase in KFe₂As₂ is substantially enhanced by the presence of nested electron and hole pockets, providing the key ingredient of high-T_c superconductivity in iron pnictide superconductors.

• Research Organization: Carnegie Institution of Washington, Washington, D.C. (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: NA0002006
• OSTI ID: 1335147
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 91, Issue 9; ISSN 1098-0121
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

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