Abstract
The London equations of superconductivity are derived from a variational principle. The derivation produces an additional scalar equation that determines the superconducting charge density. The analysis is extended to the general dissipative case by means of appropriate kinetic coefficients. After introducing the complex order parameter Ψ a time-dependent Ginzburg-Landau (GL) equation is obtained from the variational principle together with the Josephson phase relation. The real part of the GL equation is found to coincide with the additional scalar equation. Special attention is paid to a correct interpretation of the imaginary part of the GL equation. In the dissipative case the time-dependent GL equation is shown to contain two complex relaxation coefficients. The theory is supplemented by a dissipative version of the Josephson phase relation. In a special case some results given by Schmid and by Gor'kov and Eliashberg are recovered. The analysis is believed to set the scene for a microscopic derivation of a general time-dependent GL equation.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Physica B+C
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
