Four-wave mixing with Bose-Einstein condensates in nonlinear lattices
1 Faculty of Physics, University of Warsaw - ul. Hoża 69, PL-00-681 Warszawa, Poland
2 Centro de Física Teórica e Computacional and Departamento de Física, Faculdade de Ciências, Universidade de Lisboa - Avenida Professor Gama Pinto 2, Lisboa 1649-003, Portugal
Received: 3 January 2014
Accepted: 3 March 2014
The theory of the four-wave mixing in nonlinear lattices is presented. Nonlinear lattice modifies the momentum conservation condition and leaves energy conservation unaffected, contrary to the more conventional linear modulation. We study the dynamics of the moving wavepacket in the presence of a nonlinear lattice and observe the formation of two new waves which is not possible in the conventional four-wave mixing process. We design an analytical plane-wave model which agrees well with numerical simulations.
PACS: 42.65.-k – Nonlinear optics / 42.65.Hw – Phase conjugation; photorefractive and Kerr effects / 03.75.Kk – Dynamic properties of condensates; collective and hydrodynamic excitations, superfluid flow
© EPLA, 2014