AI 中文总结
研究人员将Luttinger-Ward自由能泛函扩展到含任意散射机制的无序超导体和超流体，构建了适用于多类系统的广义自由能形式，可用于外磁场下的非常规非均匀超导体等研究。
AI 中文摘要
我们将Luttinger-Ward自由能泛函扩展到具有任意散射机制的无序超导体和超流体，包括杂质无序和界面存在两种情况。在自洽t矩阵近似框架内考虑无序，从而允许任意杂质散射强度。研究表明，界面和杂质散射的自能仅通过自洽确定的费米子传播子隐式出现在泛函中。该自由能泛函在复能平面上以广义积分形式构建，通过适当选择积分路径，可涵盖基于推迟/超前传播子和Matsubara格林函数的两种形式。其可应用于空间非均匀系统、混合系统、三重态及其他非常规凝聚体、强关联费米液体等。特别有用的是基于准经典传播子的形式，该形式可应用于外塞曼磁场中的非常规非均匀单重态、三重态超导体及超流体。
英文摘要
We extend the Luttinger-Ward free energy functional to disordered superconductors and superfluids with arbitrary scattering mechanisms, including both impurity disorder and the presence of interfaces. The disorder is taken into account within the self-consistent $t$-matrix approximation, thus allowing for arbitrary impurity scattering strengths. It is shown that both the interface and the impurity scattering self-energy appear in the functional only implicitly, through self-consistently determined fermionic propagators. The free energy functional is formulated in terms of a generalized integral in the complex energy plane, which encompasses formulations both in terms of retarded/advanced propagators and in terms of Matsubara Green's functions by appropriately choosing the integration path. It can be applied, e.g., to spatially non-uniform and hybrid systems, triplet and other unconventional condensates, and strongly-correlated Fermi liquids. A particularly useful formulation in terms of the quasiclassical propagators is applied to unconventional non-uniform singlet and triplet superconductors and superfluids in an external Zeeman magnetic field.
Comments20 pages, 9 figures
