Background-free balanced optical cross correlator

摘要

A balanced optical cross correlator includes an optical waveguide, a first photodiode including a first n-type semiconductor and a first p-type semiconductor positioned about the optical waveguide on a first side of the optical waveguide's point of symmetry, and a second photodiode including a second n-type semiconductor and a second p-type semiconductor positioned about the optical waveguide on a second side of the optical waveguide's point of symmetry. A balanced receiver including first and second inputs is configured to produce an output current or voltage that reflects a difference in currents or voltages, originating from the first and the second photodiodes of the balanced cross correlator and fed to the first input and to the second input of the balanced receiver.

主权项

1. A balanced optical cross correlator comprising:
an optical waveguide including an input end, an output end, and a point of symmetry between the output end and the input end; a first photodiode including a first n-type semiconductor and a first p-type semiconductor positioned about the optical waveguide on a first side of the optical waveguide's point of symmetry; a second photodiode including a second n-type semiconductor and a second p-type semiconductor positioned about the optical waveguide on a second side of the optical waveguide's point of symmetry; a balanced receiver including a first input and a second input, with inputs having identical polarities or opposite polarities, and configured to produce an output current or voltage that reflects a difference in currents or voltages fed to the first input and to the second input; a first electrically conductive pathway coupling the first input of the balanced receiver with the first n-type semiconductor or with the first p-type semiconductor; and a second electrically conductive pathway, wherein: (I) in the case of the balanced receiver having identical input polarities, the second electrically conductive pathway couples the second input of the balanced receiver (a) with the second n-type semiconductor if the first electrically conductive pathway couples the first input with the first p-type semiconductor or (b) with the second p-type semiconductor if the first electrically conductive pathway couples the first input with the first n-type semiconductor; or (II) in the case of the balanced receiver having opposite input polarities, the second electrically conductive pathway couples the second input of the balanced receiver (a) with the second n-type semiconductor if the first electrically conductive pathway couples the first input with the first n-type semiconductor or (b) with the second p-type semiconductor if the first electrically conductive pathway couples the first input with the first p-type semiconductor.