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Universal superconducting and magnetic properties of the (CaLa)(BaLa)CuO system: a MuSR investigation

A. Keren·A. Kanigel·J. Lord·A. Amato
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Abstract

The (Ca_xLa_(1-x))(Ba_(1.75-x)La_(0.25+x))Cu_(3)O_(y) system is ideal for testing theories of high temperature superconductivity, since nearly the full range of doping is controlled by y, and T_(c)^max is continuously controlled by x, with minimal structural changes. We investigate this system with both transverse and longitudinal field MuSR. This allows us to re-examine the Uemura relation, the nature of the spontaneous magnetic fields below T_(c), and the relation between their appearance temperature T_(g) and T_(c)^max . Our major findings are: (I) the Uemura relation is respected by CLBLCO more adequately than by other cuprates, (II) T_(g) and T_(c) are controlled by the same energy scale, (III) the phase separation between hole poor and hole rich regions is a microscopic one, and (IV) spontaneous magnetic fields appear gradually with no moment size evolution.

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A. Keren, A. Kanigel, J. Lord, A. Amato. 2002-11-19. Universal superconducting and magnetic properties of the (CaLa)(BaLa)CuO system: a MuSR investigation. https://doi.org/10.1016/s0038-1098(02)00670-1

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