Two-port optical wavelength circuits composed of cascaded Mach-Zehnder interferometers with point-symmetrical configurations

Wavelength demulti/multiplexers with non-sinusoidal filtering characteristics composed of point-symmetrically connected Mach-Zehnder interferometers

“…Then we sacrifice Dl Th by DL = 0, that is, cos 2 (Dj / 2) = 1, to widen Dl Cr . This makes the WDM completely point-symmetrical, including the interferometer arms, and h is obtained from This equation means that, if 0.45 < C < 0.55, we obtain h > 0.99 and this effect widens the passband Dl Cr at the cross-port [9,10].…”

“…MZI-WDM composed of point-symmetrically connected optical couplers Figure 1 shows the configuration of a MZI-WDM composed of point-symmetrically connected optical couplers. The transfer matrices for the first optical coupler, the interferometer arms, and the second optical coupler, T C1 , T A , and T C2 , are expressed by where a and b are the complex transfer and coupling coefficients, n is the waveguide effective index, l is the wavelength in a vacuum, DL is the waveguide length difference between the interferometer arms, and Dj is the phase difference caused by DL [9,10]. We assume there are no losses.…”

Wannier-function based scattering-matrix formalism for photonic crystal circuitry

“…This would allow to investigate nonlinear circuits, for instance. Furthermore, in the area of wavelength division multiplexing/demultiplexing (WDM) [100], there are interesting concepts for the wavelength flattening of the device performance [101][102][103], which could be investigated using photonic crystal circuits. Last but not least, the application of the method to circuits in 3D photonic crystals and 2D photonic crystal slabs is certainly another interesting project.…”

A single-lithography SOI rib waveguide sensing circuit with apodized low back-reflection surface grating fiber coupling

“…Integrated silicon-on-insulator (SOI) Mach-Zehnder interferometers (MZIs) are used as modulators, 1, 2 wavelength multiplexers, 3,4 and more recently as sensors. 5,6 In all these applications, proper design of each optical component constituting the MZI is essential to reach the best performance.…”