Microscopic Derivation of Ginzburg-Landau Equations for Coexistent States of Superconductivity and Magnetism

作者：Kuboki Kazuhiro^*; Yano Keiji

来源：Journal of the Physical Society of Japan, 2012, 81(6): 064711.

DOI：10.1143/JPSJ.81.064711

• GL theory
• unconventional superconductivity
• coexistence
• proximity effect

Ginzburg-Landau (GL) equations for the coexistent states of superconductivity and magnetism are derived microscopically from the extended Hubbard model with on-site repulsive and nearest-neighbor attractive interactions. In the derived GL free energy a cubic term that couples the spin-singlet and spin-triplet components of superconducting order parameters (SCOP) with magnetization exists. This term gives rise to a spin-triplet SCOP near the interface between a spin-singlet superconductor and a ferromagnet, consistent with previous theoretical studies based on the Bogoliubov-de Gennes method and the quasiclassical Green%26apos;s function theory. In coexistent states of singlet superconductivity and antiferromagnetism it leads to the occurrence of pi-triplet SCOPs.

• 出版日期2012-6