Uniaxial pressure dependence of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="italic">T</mml:mi></mml:mrow><mml:mrow><mml:mi mathvariant="italic">c</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math>from high-resolution dilatometry of untwinned<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:mi mathvariant="normal">−</mml:mi><mml:mi mathvariant="italic">x</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Sr</mml:mi></mml:mrow><mml:mrow><mml:mi mathvariant="italic">x</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">CuO</mml:mi></mml:mrow><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>single crystals
Аннотация
We have carried out high-resolution dilatometry experiments on a series of high-quality single crystals of ${\mathrm{La}}_{2\mathrm{\ensuremath{-}}\mathit{x}}$${\mathrm{Sr}}_{\mathit{x}}$${\mathrm{CuO}}_{4}$ with various Sr content on both the under- and overdoped side of the ${\mathit{T}}_{\mathit{c}}$(x) phase diagram. A simple in situ technique was applied to prevent the usual twinning of the samples in the low-temperature orthorhombic (LTO) phase, which allows us to study the full anisotropy of the thermal expansion of the LTO phase. From the anomalies in the linear expansivities \ensuremath{\Delta}${\mathrm{\ensuremath{\alpha}}}_{\mathit{i}}$ (i=a,b,c) at ${\mathit{T}}_{\mathit{c}}$ we deduce all three uniaxial stress (${\mathit{dT}}_{\mathit{c}}$/${\mathit{dp}}_{\mathit{i}}$) and strain (${\mathit{dT}}_{\mathit{c}}$/d${\mathrm{\ensuremath{\varepsilon}}}_{\mathit{i}}$) dependences, which turn out to be large and almost cancel for hydrostatic pressure.
Перевод пока недоступен