Effect of Phase Mismatch between the Bragg Gratings on the Stability of Gap Solitons in Semilinear Dual-core System

The existence and stability of quiescent gap solitons are st udied in a semilinear dual-core optical system, in which Bragg gratings (BGs) are written on the both cores wi th a phase shift and one core has the Kerr nonlinearity, while other one is linear. When the relative g roup velocityc in the linear core is zero, three separate band gaps are observed through the spectrum analys is, including one central band gap surrounded by upper and lower band gaps. Three band gaps are entirely filled with the stationary soliton solutions. However, in case ofc is non-zero, only central band gap contains the stationary s olution. Numerical techniques are used to find the stability of the quiescent gap solitons in terms of their frequency detuning.