Type-1.5 Superconductor - Type-1.5 Superconductivity in Multiband Systems

Type-1.5 Superconductivity in Multiband Systems

In a two-band superconductor the electrons in different bands do not independently conserved thus the definition of two superconducting components is different. A two-band superconductor is described by the following Ginzburg-Landau model

F=\sum_{i,j=1,2}\frac{1}{2m} |(\nabla - ie A) \psi_i|^2 + \alpha_i |\psi_i|^2 + \beta_i|\psi_i|^4 - \eta( \psi_1\psi_2^* + \psi_1^*\psi_2) + \gamma + \nu |\psi_1|^2|\psi_2|^2 +\frac{1}{2}(\nabla \times A)^2

where again are two superconducting condensates. In multiband superconductors quite generically . When three length scales of the problem are again the London penetration length and two coherence lengths. However in this case the coherence lengths are associated with "mixed" combinations of density fields.

Read more about this topic:  Type-1.5 Superconductor

Famous quotes containing the word systems:

    “Before anything else, we need a new age of Enlightenment. Our present political systems must relinquish their claims on truth, justice and freedom and have to replace them with the search for truth, justice, freedom and reason.”
    —Friedrich Dürrenmatt (1921–1990)