Aizawa Hirohito, Kuroki Kazuhiko, Yokoyama Takehito, Tanaka Yukio
Department of Applied Physics and Chemistry, The University of Electro-Communications, Chofu, Tokyo 182-8585, Japan.
Phys Rev Lett. 2009 Jan 9;102(1):016403. doi: 10.1103/PhysRevLett.102.016403. Epub 2009 Jan 5.
We study the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state of spin fluctuation mediated pairing, and focus on the effect of coexisting charge fluctuations. We find that (i) consecutive transitions from singlet pairing to FFLO and further to S_{z}=1 triplet pairing can generally take place upon increasing the magnetic field when strong charge fluctuations coexist with spin fluctuations, and (ii) the enhancement of the charge fluctuations lead to a significant increase of the parity mixing in the FFLO state, where the triplet/singlet component ratio in the gap function can be close to unity. We propose that such consecutive pairing state transition and strong parity mixing in the FFLO state may take place in a quasi-one-dimensional organic superconductor (TMTSF)2X.
我们研究了自旋涨落介导配对的富尔德-费雷尔-拉金-奥夫钦尼科夫（FFLO）态，并关注共存电荷涨落的影响。我们发现：（i）当强电荷涨落与自旋涨落共存时，随着磁场增加，通常会发生从单重态配对到FFLO态，再进一步到Sz = 1三重态配对的连续转变；（ii）电荷涨落的增强会导致FFLO态中宇称混合的显著增加，其中能隙函数中的三重态/单重态分量比可以接近1。我们提出，这种FFLO态中的连续配对态转变和强宇称混合可能发生在准一维有机超导体（TMTSF）2X中。
