Stability of solitons in PT-symmetric couplers
  Families of analytical solutions are found for symmetric and antisymmetric solitons in the dual-core system with the Kerr nonlinearity and PT-balanced gain and loss. The crucial issue is stability of the solitons. A stability region is obtained in an analytical form, and verified by simulations, for the PT-symmetric solitons. For the antisymmetric ones, the stability border is found in a numerical form. Moving solitons of both types collide elastically. The two soliton species merge into one in the "supersymmetric" case, with equal coefficients of the gain, loss and inter-core coupling. These solitons feature a subexponential instability, which may be suppressed by periodic switching ("management"). 
Rodislav Driben (1, 2), and Boris A. Malomed (2) ((1) Jerusalem   College of Engineering - Ramat Beit HaKerem, Jerusalem, Is...
physics.optics nlin.PS