Phase Diagram of Pressure-Induced Superconductivity in EuFe2As2 Probed by High-Pressure Resistivity up to 3.2 GPa
| Autor: | Kurita, Nobuyuki, Kimata, Motoi, Kodama, Kota, Harada, Atsushi, Tomita, Megumi, Suzuki, Hiroyuki S., Matsumoto, Takehiko, Murata, Keizo, Uji, Shinya, Terashima, Taichi |
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| Rok vydání: | 2011 |
| Předmět: | |
| Zdroj: | Phys. Rev. B 83, 214513 (2011) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1103/PhysRevB.83.214513 |
| Popis: | We have constructed a pressure$-$temperature ($P-T$) phase diagram of $P$-induced superconductivity in EuFe$_2$As$_2$ single crystals, via resistivity ($\rho$) measurements up to 3.2 GPa. As hydrostatic pressure is applied, an antiferromagnetic (AF) transition attributed to the FeAs layers at $T_\mathrm{0}$ shifts to lower temperatures, and the corresponding resistive anomaly becomes undetectable for $P$ $\ge$ 2.5 GPa. This suggests that the critical pressure $P_\mathrm{c}$ where $T_\mathrm{0}$ becomes zero is about 2.5 GPa. We have found that the AF order of the Eu$^{2+}$ moments survives up to 3.2 GPa without significant changes in the AF ordering temperature $T_\mathrm{N}$. The superconducting (SC) ground state with a sharp transition to zero resistivity at $T_\mathrm{c}$ $\sim$ 30 K, indicative of bulk superconductivity, emerges in a pressure range from $P_\mathrm{c}$ $\sim$ 2.5 GPa to $\sim$ 3.0 GPa. At pressures close to but outside the SC phase, the $\rho(T)$ curve shows a partial SC transition (i.e., zero resistivity is not attained) followed by a reentrant-like hump at approximately $T_\mathrm{N}$ with decreasing temperature. When nonhydrostatic pressure with a uniaxial-like strain component is applied using a solid pressure medium, the partial superconductivity is continuously observed in a wide pressure range from 1.1 GPa to 3.2 GPa. Comment: 7 pages, 6 figures, accepted for publication in Physical Review B, selected as "Editors' Suggestion" |
| Databáze: | arXiv |
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