paper

In-plane thermal conductivity of large single crystals of Sm-substituted (Y $_{1 - x}$ Sm $_{x}$ )Ba $_{2}$ Cu $_{3}$ O $_{7 - I^´}$

arXiv:cond-mat/0602344 · doi:10.1088/0953-2048/19/8/015

Abstract

We have investigated the in-plane thermal conductivity $I^º_{ab} (T, H)$ of large single crystals of optimally oxygen-doped (Y $_{1 - x}$ ,Sm $_{x}$ )Ba $_{2}$ Cu $_{3}$ O $_{7 - I^´}$ ( $x$ =0, 0.1, 0.2 and 1.0) and YBa $_{2}$ (Cu $_{1 - y}$ Zn $_{y}$ ) $_{3}$ O $_{7 - I^´}$ ( $y$ =0.0071) as functions of temperature and magnetic field (along the c axis). For comparison, the temperature dependence of $I^º_{ab}$ for as-grown crystals with the corresponding compositions are presented. The nonlinear field dependence of $I^º_{ab}$ for all crystals was observed at relatively low fields near a half of $T_{c}$ . We make fits of the $I^º (H)$ data to an electron contribution model, providing both the mean free path of quasiparticles $ℓ_{0}$ and the electronic thermal conductivity $I^º_{e}$ , in the absence of field. The local lattice distortion due to the Sm substitution for Y suppresses both the phonon and electron contributions. On the other hand, the light Zn doping into the CuO $_{2}$ planes affects solely the electron component below $T_{c}$ , resulting in a substantial decrease in $ℓ_{0}$ .

7 pages,4 figures,1 table

In-plane thermal conductivity of large single crystals of Sm-substituted (Y1−x​Smx​)Ba2​Cu3​O7−I^´​

Abstract

In-plane thermal conductivity of large single crystals of Sm-substituted (Y $_{1 - x}$ Sm $_{x}$ )Ba $_{2}$ Cu $_{3}$ O $_{7 - I^´}$