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In this paper, designed and simulated Power Splitter (PS) integrated Mach-Zehnder interferometer (MZI) based planar waveguide devices (which is called here a PS-MZI). Moreover, we fabricated optical waveguide based on the PS-MZI for application to the biosensor. The integrated optical structure is sensitive to refractive index change induced due to the interaction of the evanescent field with an immobilized biological sample placed on one of the two arms of the interferometer. The PS-MZI sensor was preceded by a Y-junction, which splits the input power between the sensor and a reference branch to minimize the effect of optical power variations. The waveguide were optimized at a wavelength of 1550 nm and fabricated according to the design rule of 0.45 delta%, which is the difference of refractive index between the core and clad. The fabrication of PS-MZI optical waveguides was performed by a conventional planar lightwave circuit (PLC) fabrication process. The PS-MZI optical waveguides were measured of the optical characteristics for the application of biosensors.

We proposed a new kind of 1×4 optical power splitter composed of one input photonic crystal (PC) waveguide (PCW) and two PC branches with a triangular lattice of air holes. By employing the coupling between a defect region and one input, four output PCWs, the input power can be efficiently split into four output ports. The total transmittance as high as 99.4% at the wavelength 1550 nm is achieved. By modifying two holes at junction area, the input power can be almost evenly split into four parts with a bandwidth larger than 80 nm. It provides a new method and a compact model to split input power into multiple output ports in PCW devices and may find practical applications in future photonic integrated circuits.

A tunable power splitter based on metal-dielectric metal (MDM) waveguide coupled with rectangle cavity with Kerr nonlinear material is proposed. The power splitter properties are simulated by the finite-difference time-domain (FDTD) method [Y. H. Guo et al., Opt. Express19 (2011) 13831–13838]. Simple theoretically analysis and numerically calculation demonstrate that the waveguide-rectangle cavity coupled system performs a tunable plasmonic power splitter. Additionally, the output power ratio can be efficiency tuned by varying the control light intensity. Results obtained by the coupled mode theory are consistent with those from the FDTD simulation. The plasmonic splitter may become a choice for the highly integrated optical circuits.

Controllable splitting of optical power with a large splitting ratio range is often required in an integrated optical chip, e.g. for the readout of phase-shift in a slow-light sensor. In this work, we report the modeling and design of an integrated optical programmable power splitter consisting of a Y-junction with a programmable phase-shifter cascaded to a directional coupler. We used a vectorial mode solver, and a combination of a transfer matrix method with a 3D vectorial coupled-mode theory (CMT) to compute the power transfer ratio of a realistic device structure made of Si₃N₄, TEOS, and SiO₂ grown on a Si substrate. In the simulations, waveguide attenuation values derived from the measured attenuation of a prefabricated test wafer, have been taken into account. Vectorial modal fields of individual waveguides, as computed by a mode solver, were used as the basis for the CMT computation. In the simulation, an operational wavelength around 632.8 nm was assumed. Our simulations reveal that maximum power splitting ratio can be achieved when the directional coupler is operated as a 3-dB coupler with the phase-shifter set to produce a 90° phase-shift. The required coupler length for such desired operating condition is highly-dependent on the gap size. On the other hand, the inclusion of the waveguide loss and the non-parallel section of the directional coupler into the model only slightly affect the results.