Anomalous Disappearance of High-<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi>T</mml:mi></mml:mrow><mml:mrow><mml:mi>c</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math>Superconductivity at High Hole Concentration in Metallic<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">La</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn><mml:mo>−</mml:mo><mml:mi>x</mml:mi></mml:mrow></mml:msub></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Sr</mml:mi></mml:mrow><mml:mrow><mml:mi>x</mml:mi></mml:mrow></mml:msub></mml:mrow><mml:mi mathvariant="normal">Cu</mml:mi><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">O</mml:mi></mml:mrow><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>

J. B. Torrance(IBM Research - Almaden), Y. Tokura(IBM Research - Almaden), A. I. Nazzal(IBM Research - Almaden), A. Bezinge(IBM Research - Almaden), T. C. Huang(IBM Research - Almaden), S. Parkin(IBM Research - Almaden)
Physical Review Letters
August 29, 1988
Cited by 880

Abstract

Samples of ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}\mathrm{Cu}{\mathrm{O}}_{4\ensuremath{-}\ensuremath{\delta}}$ have previously shown a maximum concentration of $p=0.15$ holes per [Cu${\mathrm{O}}_{2}$] unit, because increasing $x&gt;0.15$ normally induces compensating oxygen vacancies. Annealing samples in 100 bars of oxygen pressure fills the oxygen vacancies and greatly increases the range of accessible hole concentrations, up to $p=0.40$ (or effectively ${\mathrm{Cu}}^{+2.40}$). We find that ${T}_{c}$ is constant at \ensuremath{\simeq}36 K from $p=0.15 \mathrm{to} 0.24$, where it begins to decrease. Beyond $p\ensuremath{\simeq}0.32$, superconductivity disappears, even though the samples are more conducting.


Related Papers

No related papers found

Powered by citation graph analysis