Enhanced backscattering of a dilute Bose-Einstein condensate
  We study experimentally and numerically the quasi-bidimensional transport of a $^{87}$Rb Bose-Einstein condensate launched with a velocity $v_0$ inside a disordered optical potential created by a speckle pattern. A time-of-flight analysis reveals a pronounced enhanced density peak in the backscattering direction $-v_0$, a feature reminiscent of coherent backscattering. Detailed numerical simulations indicate however that other effects also contribute to this enhancement, including a "backscattering echo" due to the position-momentum correlations of the initial wave packet. 
Guillaume Labeyrie, Tomasz Karpiuk, Jean-Fran\c{c}ois Schaff, Beno\^it   Gr\'emaud, Christian Miniatura and Dominique Delande
cond-mat.quant-gas quant-ph