Showing papers by "Nils Weimann published in 2012"

Nonolithic photonic integrated circuit

Abstract: An optical device includes a waveguide slab, first and second input port couplers, and first and second output port couplers located over a planar optical substrate. The waveguide slab has a plane of symmetry. The first and second input port couplers extend from the waveguide slab and have an input coupler pair axis located about midway between the first and second input port couplers. The input coupler pair axis is offset at a nonzero first distance from the plane of symmetry. The first and second output port couplers extend from the waveguide slab and have an output coupler pair axis located about midway between the first and second output port couplers. The output coupler pair axis is offset at a different nonzero second distance from the plane of symmetry.

Optical receiver for amplitude-modulated signals

Abstract: An optical receiver that uses a coherent optical quadrature-detection scheme to demodulate an amplitude-modulated optical input signal in a manner that enables the use of a free-running optical local-oscillator source The optical receiver employs a signal combiner that combines, into an electrical output signal, the in-phase and quadrature-phase electrical signals generated as a result of the quadrature detection of the optical input signal Depending on the frequency offset between the local- oscillator signal and the input signal, the electrical output signal produced by the signal combiner can be a desired baseband signal or an intermediate-frequency signal The latter signal can be demodulated to recover the baseband signal in a relatively straightforward manner, eg, using a conventional intermediate-frequency electrical demodulator coupled to the signal combiner