Similar setup can be implemented in SOI chip by using Y-Branches as shown below. It is a multi-input multi-output component which divides light intensity. In splitting configuration, each branch on output side will get half of the light intensity. On the other hand, in collecting configuration, incoming light will be distributed between 1st, 2nd and radiation modes, so even in 1 input - 1 output configuration, only half of the intensity will be delivered to output. There is no phase shifting due to Y-Branches.