Ferromagnetic 0–πJosephson junctions |
| |
Authors: | M. Weides H. Kohlstedt R. Waser M. Kemmler J. Pfeiffer D. Koelle R. Kleiner E. Goldobin |
| |
Affiliation: | 1.Center of Nanoelectronic Systems for Information Technology (CNI),Research Centre Jülich,Jülich,Germany;2.Physikalisches Institut – Experimentalphysik II,Universit?t Tübingen,Tübingen,Germany |
| |
Abstract: | We present a study on low-Tc superconductor-insulator-ferromagnet-superconductor (SIFS) Josephson junctions. SIFS junctions have gained considerable interest in recent years because they show a number of interesting properties for future classical and quantum computing devices. We optimized the fabrication process of these junctions to achieve a homogeneous current transport, ending up with high-quality samples. Depending on the thickness of the ferromagnetic layer and on temperature, the SIFS junctions are in the ground state with a phase drop of either 0 or π. By using a ferromagnetic layer with variable step-like thickness along the junction, we obtained a so-called 0–π Josephson junction, in which 0 and π ground states compete with each other. At a certain temperature the 0 and π parts of the junction are perfectly symmetric, i.e. the absolute critical current densities are equal. In this case the degenerate ground state corresponds to a vortex of supercurrent circulating clock- or counterclockwise and creating a magnetic flux which carries a fraction of the magnetic flux quantum Φ0. PACS 74.50.+r; 74.78.Fk; 74.81.-g; 85.25.Cp |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|