Inhomogeneous electronic structure probed by spin-echo experiments in the electron doped high-Tc superconductor Pr_{1.85}Ce_{0.15}CuO_{4-y}

F. Zamborszky; G. Wu; J. Shinagawa; W. Yu; H. Balci; R. L. Greene; W. G. Clark; S. E. Brown

doi:10.1103/physrevlett.92.047003

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Inhomogeneous electronic structure probed by spin-echo experiments in the electron doped high-Tc superconductor Pr_{1.85}Ce_{0.15}CuO_{4-y}

F. Zamborszky·G. Wu·J. Shinagawa·W. Yu·H. Balci·R. L. Greene·W. G. Clark·S. E. Brown

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Abstract

63Cu nuclear magnetic resonance (NMR) spin-echo decay rate (T_2^{-1}) measurements are reported for the normal and superconducting states of a single crystal of Pr_{1.85}Ce_{0.15}CuO_{4-y} (PCCO) in a magnetic field B_0=9T over the temperature range 2K<T<200K. The spin-echo decay rate is temperature-dependent for T<55K, and has a substantial dependence on the radio frequency (rf) pulse parameters below T~25K. This dependence indicates that T_2^{-1} is strongly effected by a local magnetic field distribution that can be modified by the rf pulses, including ones that are not at the nuclear Larmor frequency. The low-temperature results are consistent with the formation of a static inhomogeneous electronic structure that couples to the rf fields of the pulses.

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F. Zamborszky, G. Wu, J. Shinagawa, W. Yu, H. Balci, R. L. Greene, W. G. Clark, S. E. Brown. 2003-07-01. Inhomogeneous electronic structure probed by spin-echo experiments in the electron doped high-Tc superconductor Pr_{1.85}Ce_{0.15}CuO_{4-y}. https://doi.org/10.1103/physrevlett.92.047003

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