Nonlinear dynamics of wave packets in PT-symmetric optical lattices near   the phase transition point
  Nonlinear dynamics of wave packets in PT-symmetric optical lattices near the phase-transition point are analytically studied. A nonlinear Klein-Gordon equation is derived for the envelope of these wave packets. A variety of novel phenomena known to exist in this envelope equation are shown to also exist in the full equation including wave blowup, periodic bound states and solitary wave solutions. 
Sean Nixon, Yi Zhu, and Jianke Yang
physics.optics nlin.PS