Chameleon field and the late time acceleration of the universe
  In the present work, it is shown that a chameleon scalar field having a nonminimal coupling with dark matter can give rise to a smooth transition from a decelerated to an accelerated phase of expansion for the universe. It is surprising to note that the coupling with the chameleon scalar field hardly affects the evolution of the dark matter sector, which still redshifts as $a^{-3}$. 
Narayan Banerjee, Sudipta Das, Koyel Ganguly