论文标题
金属自旋冰中的声子热大厅效应
Phonon thermal Hall effect in a metallic spin ice
论文作者
论文摘要
尽管基础机制仍然存在争议，但声子可以在各种材料中产生热厅效应已成为常识。我们研究纵向$κ_{xx} $和横向$κ_{xy} $ pr $ _2 $ _2 $ ir $ _2 $ o $ $ _7 $的热导率，这是一种金属旋转冰的类似物。尽管存在移动电荷载体，但我们发现$κ_{xx} $和$κ_{xy} $都由声子主导。 $κ_{xx} $的$ t/h $缩放明确地表明，纵向热电流极大地阻碍了声子上的paramagnetic旋转上的共振散射。冷却后，共振散射受自旋冰相关的发展，$κ_{xx} $在田间方向方面以各向异性方式偏离缩放。令人惊讶的是，一组$κ_{xx} $和$κ_{xy} $数据清楚地表明，$κ_{xy} $与$κ_{xx} $相关，其响应在其对磁场的响应中，包括$ t/h $ scaleing的成功及其在低温下的失败。这种显着的相关性提供了可靠的证据，表明不可或缺的作用是通过旋转散射不仅在阻碍纵向热传导的情况下发挥的，而且还用于产生横向反应。
It has become common knowledge that phonons can generate thermal Hall effect in a wide variety of materials, although the underlying mechanism is still controversial. We study longitudinal $κ_{xx}$ and transverse $κ_{xy}$ thermal conductivity in Pr$_2$Ir$_2$O$_7$, which is a metallic analogue of spin ice. Despite the presence of mobile charge carriers, we find that both $κ_{xx}$ and $κ_{xy}$ are dominated by phonons. A $T/H$ scaling of $κ_{xx}$ unambiguously reveals that longitudinal heat current is substantially impeded by resonant scattering of phonons on paramagnetic spins. Upon cooling, the resonant scattering is strongly affected by a development of spin ice correlation and $κ_{xx}$ deviates from the scaling in an anisotropic way with respect to field directions. Strikingly, a set of the $κ_{xx}$ and $κ_{xy}$ data clearly shows that $κ_{xy}$ correlates with $κ_{xx}$ in its response to magnetic field including a success of the $T/H$ scaling and its failure at low temperature. This remarkable correlation provides solid evidence that an indispensable role is played by spin-phonon scattering not only for hindering the longitudinal heat conduction, but also for generating the transverse response.
