Controllable coupling of superconducting flux qubits |
| |
Authors: | van der Ploeg S H W Izmalkov A van den Brink Alec Maassen Hübner U Grajcar M Il'ichev E Meyer H-G Zagoskin A M |
| |
Affiliation: | Institute for Physical High Technology, P.O. Box 100239, D-07702 Jena, Germany. |
| |
Abstract: | We have realized controllable coupling between two three-junction flux qubits by inserting an additional coupler loop between them, containing three Josephson junctions. Two of these are shared with the qubit loops, providing strong qubit-coupler interaction. The third junction gives the coupler a nontrivial current-flux relation; its derivative (i.e., the susceptibility) determines the coupling strength J, which thus is tunable in situ via the coupler's flux bias. In the qubit regime, J was varied from approximately 45 (antiferromagnetic) to approximately -55 mK (ferromagnetic); in particular, J vanishes for an intermediate coupler bias. Measurements on a second sample illuminate the relation between two-qubit tunable coupling and three-qubit behavior. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|