An investigation into density-wave propagation within high-temperature superconducting plasmas for use in creating traveling-wave devices

Nonlinear Density Wave Propagation in Layered Superconducting Plasmas

“…Recently Bunch and Grow [1] have investigated the linear propagation of density waves in a superconducting plasma by using the London theory [2] and the two fluid GorterCasimir [3] model to describe a superconducting plasma. Ali and Shah [4] extended this work to explore the propagation of density waves in a medium consisting of periodically alternating layers of a superconducting plasma.…”

“…The shortcoming of such phenomenological theories is that these are too general to provide an actually rigorous explanation of the mechanism of HTS. Bunch and Grow [1] have noted the applications of the phenomenological theories in devices using superconductors and have enumerated some of the advantages of using superconductors in active devices and have stressed the possible importance of travelling wave behavior of superconducting electrons in these devices.…”

“…In this work we have attempted to explore the nonlinear wave propagation properties of density waves in a periodically layered superconducting plasma (each layer is say a YBCO superconductor described by the London and two fluid model [1]). We employ a standard perturbation and scaling technique to derive the nonlinear Schro È dinger (NLS) equation which governs the propagation of density waves in the superconducting medium.…”

“…The properties of the nonlinear wave for a layered structure consisting of alternating superconductor layers are investigated using the Kronig-Penney model. As in the work of Bunch and Grow [1] and Ali and Shah [4] here, too, we make use of the London model along with the two fluid model to describe the superconducting plasma which can be thought to be composed of both normal and superfluid electrons. The two fluid model takes losses into account, since one fluid is related to the superconducting electrons and the other to the semiconducting electrons.…”

“…This approach is further justified since high T c ceramics exhibit metallic properties along the superconducting plane (ab-plane) and semiconductor characteristics along the c-plane. Bunch and Grow [1] have noted that this approach may have applications in the use of superconductors in travelling wave devices. The advantages of such a device are, that no electron focusing structure is needed, no cathode is necessary.…”