Dynamic behavior of the supercurrent in mesoscopic Josephson junctions in the presence of a nonclassical electromagnetic field
Zou Jian, Shao Bin, Xing Xiu-San · Physical review. B, Condensed matter · 1997
The dynamic behavior of the supercurrent in mesoscopic Josephson junctions interacting with various nonclassical electromagnetic fields (NEMF) is investigated. It is shown that for squeezed number states, squeezed states, and a superposition of two coherent states, the supercurrent exhibits a collapse and revival (CR) phenomenon that is well known in the context of quantum optics. For coherent states and number states, this phenomenon does not occur. This CR phenomenon, which is due to the granular nature of the field, is also absent if the field is considered classically. The dynamic behavior of the supercurrent fluctuation is also studied and it is found that, generally, when the fluctuation is large, the supercurrent exhibits collapses, and, when the fluctuation is small, the supercurrent exhibits revivals. Finally, the amplitude of current-voltage steps for various NEMF's are studied in some detail.