Laboratoire de Physique de la Matière Condensée, Département de Physique, Faculté des Sciences de Tunis, Université Tunis El Manar, Campus Universitaire, 1060 Tunis, Tunisia.
J Phys Condens Matter. 2011 Nov 23;23(46):464205. doi: 10.1088/0953-8984/23/46/464205. Epub 2011 Nov 3.
Several experimental studies have shown the presence of spatially inhomogeneous phase coexistence of superconducting and non-superconducting domains in low dimensional organic superconductors. The superconducting properties of these systems are found to be strongly dependent on the amount of disorder introduced in the sample regardless of its origin. The suppression of the superconducting transition temperature T(c) shows a clear discrepancy with the result expected from the Abrikosov-Gor'kov law giving the behavior of T(c) with impurities. On the basis of the time dependent Ginzburg-Landau theory, we derive a model to account for this striking feature of T(c) in organic superconductors for different types of disorder by considering the segregated texture of the system. We show that the calculated T(c) quantitatively agrees with experiments. We also focus on the effect of superconducting fluctuations on the upper critical fields H(c2) of layered superconductors showing slab structure where superconducting domains are sandwiched by non-superconducting regions. We found that H(c2) may be strongly enhanced by such fluctuations.
一些实验研究表明，在低维有机超导体中存在超导相与非超导相的空间非均匀共存。这些系统的超导性质被发现强烈依赖于样品中引入的无序量，而与无序的来源无关。超导转变温度 T(c) 的抑制与 Abrikosov-Gor'kov 定律所预期的与杂质有关的 T(c)行为明显不符。基于时间相关的金兹堡-朗道理论，我们通过考虑系统的隔离纹理，推导出一个模型来解释有机超导体中 T(c)的这一显著特征，以不同类型的无序为基础。我们表明，计算出的 T(c)与实验结果定量一致。我们还关注了超导涨落对具有夹层结构的层状超导体的上临界场 H(c2)的影响，其中超导畴被非超导区域夹在中间。我们发现，这种涨落可能会强烈增强 H(c2)。
