论文标题
与旋转密度波顺序共存的超导体中的热传输
Thermal Transport in Superconductors with coexisting Spin Density Wave Order
论文作者
论文摘要
我们在二维系统中研究热传输，并共存$ s $ - 或$ d $ - 波超导（SC）和旋转密度波（SDW）订单。我们用$ \ mathbf {q} =（π，π）$ sdw排序分析了一个紧密结合的平方晶格的共存阶段的性质。电子热导率是在玻尔兹曼动力学理论框架内计算的，它使用天生的近似值用于杂质散射碰撞积分。我们描述了Fermi表面（FS）拓扑，SC和SDW阶订单参数之间的竞争，共存阶段中零能激励的存在或不存在对各种解析状态的导热率的低温行为。我们提出了定性分析和完全数值的结果，这些结果表明，界线SDW顺序中出现的各种SC状态的热传输特征是完全不同的，并且取决于SDW嵌套载体$ \ MATHBF {Q} $在翻译下的SC订单参数的对称特性。 {$（π，π）$ - sdw和$ d_ {x^2-y^2} $配对状态的组合产生了完全散发的激发，而$（π，π）$ - sdw与$ d_ {xy} $或$ s $ s $ s $ -wave配对状态的共存可能始终具有gapitations。在共存阶段，出现特殊的稳定dirac节点点，而SC顺序不会被SC顺序覆盖，从而导致有限的残留热电导率。
We study thermal transport in a two-dimensional system with coexisting $s$- or $d$-wave Superconducting (SC) and Spin Density Wave (SDW) orders. We analyse the nature of coexistence phase in a tight-binding square lattice with $\mathbf{Q}=(π,π)$ SDW ordering. The electronic thermal conductivity is computed within the framework of the Boltzmann kinetic theory, using Born approximation for the impurity scattering collision integral. We describe the influence of the Fermi surface (FS) topology, the competition between the SC and SDW order parameters, the presence or absence of zero energy excitations in the coexistence phase, on the low temperature behavior of thermal conductivity of the various paring states. We present qualitative analytical, and fully numerical results that show that the heat transport signatures of various SC states emerging from collinear SDW order are quite distinct, and depend on the symmetry properties of the SC order parameter under translation by the SDW nesting vector $\mathbf{Q}$. {A combination of $(π,π)$-SDW and the $d_{x^2-y^2}$ pairing state results in fully gapped excitations, whereas $(π,π)$-SDW co-existing with either $d_{xy}$ or $s$-wave pairing states may always have gapless excitations. There appear special stable Dirac nodal points that are not gapped by the SC order in the coexistence phase, resulting in finite residual heat conductivity.
