Patent ID: 6603893
Filing Date: 2003-08-05
Classification: G02B,G02F

Abstract:
An apparatus, comprising:first and second multi-mode interference (MMI) splitting devices in a semiconductor substrate, first and second outputs of the first MMI splitting device optically coupled to first and second inputs, respectively, of the second MMI splitting device; and first and second phase control devices in the semiconductor substrate, the first and second phase control devices having first and second plurality of trench capacitors, respectively, the first input of the second MMI splitting device optically coupled to the first output of the first MMI splitting device through the first phase control device, the second input of the second MMI splitting device optically coupled to the second output of the first MMI splitting device through the second phase control device, a first input of the first MMI splitting device selectively optically coupled to first and second outputs of the second MMI splitting device in response to the first and second phase control devices, a second input of the first MMI splitting device selectively optically coupled to the first and second outputs of the second MMI splitting device in response to the first and second phase control devices.