Parametric amplification of matter waves in periodically translated optical lattices.
We observe the sudden growth of small classes of Bloch waves from atomic Bose-Einstein condensates held in periodically translated optical lattices. The effect is explained by narrowband parametric amplification of Bloch waves from noise, due to phase-matched scattering of atom pairs out of the condensate. Amplification occurs above a well-defined modulation threshold, described by dynamic shaping of single-particle band structure.
Gemelke
N
N
Department of Physics, Stanford University, Stanford, California 94305, USA.
Sarajlic
E
E
Bidel
Y
Y
Hong
S
S
Chu
S
S