Specific temperature dependence of pseudogap in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>YBa</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi>Cu</mml:mi><mml:mn>3</mml:mn></mml:msub><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mrow><mml:mn>7</mml:mn><mml:mo>−</mml:mo><mml:mi>δ</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math> nanolayers

The pseudogap (PG) derived from the analysis of the excess conductivity ${\ensuremath{\sigma}}^{\ensuremath{'}}(T)$ in superlattices and double-layer films of ${\text{YBa}}_{2}{\text{Cu}}_{3}{\text{O}}_{7\ensuremath{-}\ensuremath{\delta}}{\text{-PrBa}}_{2}{\text{Cu}}_{3}{\text{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ (YBCO-PrBCO), prepared by pulsed laser deposition, is studied for the first time. The ${\ensuremath{\sigma}}^{\ensuremath{'}}(T)$ analysis has been performed within the local-pair (LP) model based on the assumption of the paired fermion (LPs) formation in the cuprate high-${T}_{c}$ superconductors (cuprates) below the representative temperature ${T}^{*}\ensuremath{\gg}{T}_{c}$ resulting in the PG opening. Within the model, the temperature dependencies of the PG, ${\mathrm{\ensuremath{\Delta}}}^{*}(T)$, for the samples with different number of the PrBCO layers (${N}_{\mathrm{Pr}}$) were analyzed in the whole temperature range from ${T}^{*}$ down to ${T}_{c}$. Near ${T}_{c},\phantom{\rule{4pt}{0ex}}{\ensuremath{\sigma}}^{\ensuremath{'}}(T)$ was found to be perfectly described by the Aslamazov--Larkin (AL) and Hikami--Larkin (HL) [Maki--Thompson (MT) term] fluctuation theories, suggesting the presence of superconducting fluctuations in a relatively large (up to 15 K) temperature range above ${T}_{c}$. All sample parameters were found to change with increase of ${N}_{\mathrm{Pr}}$, finally resulting in the appearance of the pronounced maximum of ${\mathrm{\ensuremath{\Delta}}}^{*}(T)$ at high temperatures. The result is most likely due to increasing influence of the intrinsic magnetism of PrBCO (${\ensuremath{\mu}}_{\mathrm{Pr}}\ensuremath{\approx}4{\ensuremath{\mu}}_{B}$) and suggests the possibility to search in that way the change of interplay between the superconductivity and magnetism in cuprates.

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