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High Pressure Study of Structural Phase Transitions and Superconductivity in La1.48Nd0.4Sr0.12CuO4

M. K. Crawford·R. L. Harlow·S. Deemyad·V. Tissen·J. S. Schilling·E. M. McCarron·S. W. Tozer·D. E. Cox·N. Ichikawa·S. Uchida·Q. Huang
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Abstract

We have determined the crystal structures and superconducting transition temperatures of La1.48Nd0.4Sr0.12CuO4 under nearly hydrostatic pressures in diamond anvil cells to 5.0 GPa and 19.0 GPa, respectively. Synchrotron x-ray powder diffraction measurements were used to establish the pressure-temperature structural phase diagram. Under pressure the superconducting transition temperature increases rapidly from Tc = 3 K to a maximum value of 22 K at 5 GPa, a pressure slightly greater than that required to stabilize the undistorted I4/mmm structure in the superconducting state. Increasing the pressure further to 19 GPa leads to a decrease in Tc to ~12 K. These results are discussed in relation to earlier high pressure measurements for similar materials.

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M. K. Crawford, R. L. Harlow, S. Deemyad, V. Tissen, J. S. Schilling, E. M. McCarron, S. W. Tozer, D. E. Cox, N. Ichikawa, S. Uchida, Q. Huang. 2004-12-27. High Pressure Study of Structural Phase Transitions and Superconductivity in La1.48Nd0.4Sr0.12CuO4. https://doi.org/10.1103/physrevb.71.104513

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