Fig. 1 (IMAGE) Science China Press Caption Inserting the second BS when the two sub-waves have an encounter, as in (a), can produce two resultant sub-waves, as in (b), if two-sub waves inside the MZI are in-phase. Credit ©Science China Press Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.