Josephson Currents In Two-Gap Superconductor-Insulator- Superconductor Junctions

<p>As a way to investigate the transport property of superconductor-insulator-superconductor (SIS) junction with two-gap superconductors such as MgB2 and iron superconductors, we study the microscopic structure of the Josephson current in a tunnel junction with a very narrow quasi-classical barrier. Also, the possibility of mid-gap states in two-gap superconductor is investigated, and their effects on the current-phase relation as well as the current density characteristics are studied. In the SIS break junction, mid-gap states appear at the Superconductor-Insulator interfaces due to an abrupt change in the superconducting order parameter, indicating that the two-gap superconductor SIS junction can yield a rich bound state structure in the energy gap. In this work, I study the mid-gap bound state energy of the two-gap superconductor-based short Josephson junctions. Also, I study the tunneling currents through the mid-gap states theoretically to estimate the effects of these bound states on the current-phase characteristics and the critical Josephson current.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Physics & Astrophysics

Year

2013

Author dc:creator

• Bahrainirad, Ladan

Contributors dc:contributor

• Ju H Kim

• Bound state energy, interference effect, Josephson current, Mid-gap states, SUPERCONDUCTOR-INSULATOR- SUPERCONDUCTOR JUNCTIONS, Two- gap Superconductor

Repository record dc:identifier

https://commons.und.edu/theses/1395

OAI identifier oai:identifier

oai:commons.und.edu:theses-2396