Thermalization of isolated Bose-Einstein condensate under a parity-time-symmetric environment

The postulates of the eigenstate thermalization hypothesis (ETH) expresses that the thermalization occurs due to the individual eigenstate of the system’s Hamiltonian. But the ETH sheds no light on the dynamics that lead toward the thermalization. In this paper, we observe the thermalization of a Bose–Einstein condensate (BEC) confined in an optical lattice potential that is embedded on the harmonic trap. Such optical lattice potential offers local friction to the oscillating BEC. The spread in the temporal density plot of BEC shows the thermalization of the BEC. Moreover, we observe that the presence of a parity–time (PT)-symmetric potential greatly influences the BEC dynamics and the thermalization of the system. The presence of a PT-symmetric potential offers a way to manipulate the mean position of the BEC to a desired location and for a desired length of time.