Possible manifestation of spin fluctuations in the temperature behavior of resistivity in Sm_{1.85}Ce_{0.15}CuO_4 thin films

Abstract

A pronounced step-like (kink) behavior in the temperature dependence of resistivity $\rho (T)$ is observed in the optimally-doped $S{m}_{1.85}C{e}_{0.15}Cu{O}_4$ thin films around $T_{sf}=87K$ and attributed to manifestation of strong spin fluctuations induced by $S{m}^{3+}$ moments with the energy $\hslash {\omega }_{sf}=k_B{T}_{sf}\simeq 7meV$. In addition to fluctuation induced contribution ${\rho }_{sf}(T)$ due to thermal broadening effects (of the width ${\omega }_{sf}$), the experimental data are found to be well fitted accounting for residual (zero-temperature) ${\rho }_{res}$, electron-phonon ${\rho }_{e-ph}(T)=AT$ and electron-electron ${\rho }_{e-e}(T)=B{T}^2$ contributions. The best fits produced ${\omega }_p=2.1meV$, ${\tau }_0^{-1}=9.5\times 10^{-14}{s}^{-1}$, $\lambda =1.2$, and $E_F=0.2eV$ for estimates of the plasmon frequency, the impurity scattering rate, electron-phonon coupling constant, and the Fermi energy, respectively.

6 pages (REVTEX4), 2 EPS figures; accepted for publication in JETP Letters

References in corpus (3)

• Spin correlations in the electron-doped high-transition-temperature superconductor Nd{2-x}Ce{x}CuO{4+/-delta}
• Field-dependent diamagnetic transition in magnetic superconductor $S{m}_{1.85}C{e}_{0.15}Cu{O}_{4-y}$
• Probing pairing symmetry of Sm_{1.85}Ce_{0.15}CuO_4 via highly-sensitive voltage measurements: Evidence for strong impurity scattering