Pressure-induced shift of T$_c$ in K$_x$Sr$_{1-x}$Fe$_2$As$_2$ (x=0.2, 0.4, 0.7): Analogy to the high-T$_c$ cuprate superconductors

Melissa Gooch; Bing Lv; Bernd Lorenz; Arnold M. Guloy; Ching-Wu Chu

doi:10.1103/physrevb.78.180508

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arXiv · 0809.2054

Pressure-induced shift of T$_c$ in K$_x$Sr$_{1-x}$Fe$_2$As$_2$ (x=0.2, 0.4, 0.7): Analogy to the high-T$_c$ cuprate superconductors

Melissa Gooch·Bing Lv·Bernd Lorenz·Arnold M. Guloy·Ching-Wu Chu

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Abstract

The systematic pressure shifts of T_c were investigated in the whole phase diagram of the FeAs-based superconducting compound K_xSr_{1-x}Fe_2As_2. Different regions, arising from corresponding responses of T$_c$ to pressure (dT_c/dp>0, =0, or <0), can be clearly distinguished. This reveals an interesting similarity of the FeAs superconductors and the high-T_c cuprates. This behavior is a manifestation of the layered structure of the FeAs compounds and the pressure-induced charge transfer between the (Fe_2As_2) and (K/Sr) layers. The coexistence of superconductivity and spin-density wave behavior were also observed, and the pressure effects on the latter is explored.

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Melissa Gooch, Bing Lv, Bernd Lorenz, Arnold M. Guloy, Ching-Wu Chu. 2008-11-26. Pressure-induced shift of T$_c$ in K$_x$Sr$_{1-x}$Fe$_2$As$_2$ (x=0.2, 0.4, 0.7): Analogy to the high-T$_c$ cuprate superconductors. https://doi.org/10.1103/physrevb.78.180508

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