| Autor: |
A V Shcherbakova, K G Fedorov, K V Shulga, V V Ryazanov, V V Bolginov, V A Oboznov, S V Egorov, V O Shkolnikov, M J Wolf, D Beckmann, A V Ustinov |
| Předmět: |
|
| Zdroj: |
Superconductor Science & Technology; Feb2015, Vol. 28 Issue 2, p1-1, 1p |
| Abstrakt: |
We describe fabrication and testing of composite flux qubits combining Nb- and Al-based superconducting circuit technology. This hybrid approach to making qubits allows for employing π-phase shifters fabricated using well-established Nb-based technology of superconductor–ferromagnet–superconductor Josephson junctions. The important feature here is to obtain high interface transparency between Nb and Al layers without degrading sub-micron shadow mask. We achieve this by in situ Ar etching using e-beam gun. Shadow-evaporated Al/AlOx/Al Josephson junctions with Nb bias pads show the expected current–voltage characteristics with reproducible critical currents. Using this technique, we fabricated composite Nb/Al flux qubits with Nb/CuNi/Nb π-shifters and measured their magnetic field response. The observed offset between the field responses of the qubits with and without π-junction is attributed to the π phase shift. The reported approach can be used for implementing a variety of hybrid Nb/Al superconducting quantum circuits. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
