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arXiv · 1008.1847

Chirp Control of Sinusoidal Lattice Modes in Bose-Einstein Condensate

Abstract

A parametrically forced Bose-Einstein condensate (BEC) is studied in the mean field approach for the case of a general moving optical lattice. The interaction between the atoms in the condensate and the time dependent lattice potential leads to a novel propagating superfluid matter wave, which can be controlled through chirp management. This system, when placed in a trap, accelerates and undergoes rapid nonlinear compression, controlled by the chirp. The density achieves its maximum, precisely when the matter wave changes direction. A dynamical phase transition is identified, which takes the superfluid phase to an insulating state. The exact expression for energy is obtained and analyzed in detail to gain physical understanding of the chirp management of the sinusoidal excitations and also the dynamical phase transition.

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Priyam Das, Prasanta K. Panigrahi. 2010-08-11. Chirp Control of Sinusoidal Lattice Modes in Bose-Einstein Condensate. https://arxiv.org/abs/1008.1847

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