Design, simulation, and fabrication of nano-scale silicon-on-insulator (SOI) integrated photonic phased array switch elements (IPPAS) utilizing nanoelectromechanical systems (NEMS)

Abstract

The goal of this research is to introduce the design and simulation of a novel 2×2 SOI integrated photonic phased array switch. Under-etched NEMS-operated slot waveguides are used as the active phase shifters offering the benefits of compact size and low power consumption. The design of the NEMS-operated phase shifter has been validated by numerical analysis and simulation. The finite difference mode three-dimensional full-vectorial solver of FIMMPROP is used for the simulation. The designed NEMS-operated phase shift element is only 349 µm in length, exhibits an excess loss of about 1.1 dB and provides a phase shift of 180º. Straight transition slot waveguide couplers with high efficiency of about 96.7% have been designed to couple the NEMS-operated phase shifters to standard unslotted waveguides. The 2×2 MMI (multimode interference) couplers used in the switch element feature a compact size of 4 µm × 61.2 µm, have a small excess loss of about 0.155 dB and minimal imbalance of about -0.004 dB. The NEMS-operated phase shifters are located on the sides of the switch with their outermost electrode bond pads. Optical interferogram response is utilized for the testing of the designed phase shifters.

Design of a compact tunable wavelength division multiplexing photonic phased array switch using nano electromechanical systems on a silicon-on-insulator integration platform

“…2 follows the design procedure disclosed in [3]. It consists of 15 cascaded under-etched slot waveguides capable of achieving up to 180º of phase shift difference; transitions slot couplers that are 96.7% efficient according to simulations and the probing structure to bias the electrically isolated silicon beam of the phase shifter.…”

“…The design is conducted by simulating the effective index of the under-etched slotted nanowire waveguide versus the slot width and then using these data in the nanoelectromechanical nonlinear numerical model presented in [1] and [3]. …”

“…The designs of the -3dB and crossover 2×2 MMI couplers are justified in [3]. A maximum width of 2 µm is reserved to each port of the -3 dB 2×2 MMI coupler.…”

“…Paiam and MacDonald [2] presented designs of wavelength division multiplexed (WDM) wavelength routing (de)multiplexers using splitter/combiner multimode interference (MMI) couplers with path length imbalanced interconnection networks between them. We presented the concept of phased array switches in [3] where a novel 2×2 Integrated Photonic Phased Array Switch (IPPAS) element with path length differences is used to associate the shift in the resulted output wavelength interferogram patterns with the phase shift differences achieved by the NEMS-operated under-etched slot waveguides. In this work, we present the use of the NEMSoperated phase shifters and path length differences in a 4×4 IPPAS element achieving tunable WDM wavelength routing functionality.…”

New dynamic silicon photonic components enabled by MEMS technology

“…[6][7][8][9][10][11][12][13][14] In particular, through the manipulation of evanescent fields of guided waves, tunable true time delays and waveguide dispersion can be achieved. Photonic MEMS can thus be an enabling technology for large reconfigurable photonic circuits.…”