Effect of the optical field in squeezed coherent state on the entanglement of coupling qubits

We investigate the interaction between the optical field in squeezed coherent state and the coupling qubits. By means of numerical calculation, we discuss the effects of coherent amplitude, relative phase of the coupling qubits, squeezing parameter and azimuth angle on the concurrence and the probability of two qubits simultaneously in the excited state. When the relative phase is zero, entanglement death will occur, which can be avoided through increasing the relative phase. Larger value the relative phase takes, more the concurrence will be far away from entanglement death. Moreover, smaller squeezing parameter will also help to entanglement maintaining. The research indicates that in the optical filed of squeezed coherent states, the entanglement death can be avoided completely through manipulating the relative phase of the coupling qubits that initially in the entangled coherent states.