摘要
We propose to create pairs of semifluxons starting from a flat-phase state in long, optical 0-pi-0 Josephson junctions formed with internal electronic states of atomic Bose-Einstein condensates. In this optical system, we can dynamically tune the length a of the p junction, the detuning delta of the optical transition, or the strength Omega(0) of the laser coupling to induce transitions from the flat-phase state to such a semifluxon-pair state. Similarly as in superconducting 0-pi-0 junctions, there are two, energetically degenerate semifluxon-pair states. A linear mean-field model with two internal electronic states explains this degeneracy and shows the distinct static field configuration in a phase diagram of the junction parameters. This optical system offers the possibility to dynamically create a coherent superposition of the distinct semifluxon-pair states and observe macroscopic quantum oscillation. DOI: 10.1103/PhysRevA.87.021602
- 出版日期2013-2-13