Josephson oscillation in the open two-site Bose-Hubbard system

Kolovsky, A.R.// Europhysics Letters//

DOI: 10.1209/0295-5075/ac8cae

We analyze Josephson's oscillation of Bose particles in the open two-site Bose-Hubbard system. First, we excite the system from the vacuum state into a state suitable for observing the oscillation by using a special protocol for external driving. Next, we switch off the driving and observe the oscillation. It is shown that the main mechanism for the decay of Josephson's oscillation is the dephasing due to the fluctuating number of particles in open systems. An analytical estimate for the decay time is obtained.