QUANTUM EFFECTS IN THE COLLECTIVE LIGHT SCATTERING FROM A BOSE-EINSTEIN CONDENSATE

N. Piovella, M. Gatelli, R. Bonifacio

Nguyen Viet Hung

In this paper, we investigate the collective excitations of an attractively interacting Bose–Einstein condensate confined in a two-channel potential. Using the Bogoliubov approximation, we derive the Bogoliubov–de Gennes equations and determine the excitation spectrum numerically. Two distinct modes are identified: the well-known Josephson mode, associated with periodic inter-channel tunneling, and a novel antisymmetric translational mode, describing out-of-phase oscillations of the condensate center of mass. Unlike conventional dipole oscillations, the latter arises from the interplay between inter-channel coupling and attractive nonlinearity and does not follow the Kohn theorem. We then employ the variational approximation to describe the condensate dynamics under these excitations and to extract the corresponding mode frequencies. The results are further validated by real-time simulations of the governing Gross–Pitaevskii equations, showing good agreement between analytical and numerical approaches.

Yu Guo, RONG-SHENG QU

An optical scheme of the quantum teleportation of superposed coherent states from light pulse to the atoms in Bose–Einstein condensate in terms of optical elements is presented. Beam splitters, photodetectors, cross-Kerr medium, and coherent state sources are needed in this scheme. The probability of successful teleportation is also obtained.

S. Inouye, A. P. Chikkatur, Dan Stamper-Kurn +3 more

Bernard Roulet, Ph. Nozières

Yu. A. Avetisyan, Evgenii Dmitrievich Trifonov