Sensitivity improvement of broadband electro-optic polymer-based optical phase modulator using 1D and 2D photonic crystal structures

Abstract

This Letter introduces the design and simulation of a microstrip-line-based electro-optic (EO) polymer optical phase modulator (PM) that is further enhanced by the addition of photonic crystal (PhC) structures that are in close proximity to the optical core. The slow-wave PhC structure is designed for two different material configurations and placed in the modulator as a superstrate to the optical core; simulation results are depicted for both 1D and 2D PhC structures. The PM characteristics are modeled using a combination of the finite element method and the optical beam propagation method in both the RF and optical domains, respectively. The phase-shift simulation results show a factor of 1.7 increase in an effective EO coefficient (120 pm/V) while maintaining a broadband bandwidth of 40 GHz.OCIS The combination of silicon photonics and electro-optic (EO) polymers in optical devices enables the fabrication of high-level photonic device integration [1] using CMOS compatible nanofabrication technology [2] . The use of EO polymers allows for a large EO coefficient (r 33 ), very low dispersion, a fast response time (<1 ps), and simple fabrication [3,4] . Compared to the limitations of traditional inorganic crystal modulators in terms of the EO coefficient (r 33 ∼ 30 pm∕V), the use of a synthesized EO polymer allows a higher EO coefficient (r 33 ¼ 138 pm∕V at 1550 nm) due to the progress of chromophore synthesis and the high efficiency of poling; this improvement allows for a better modulation efficiency [5] and extremely high modulation speeds of over 150 GHz [6,7]

Coupling length variation and multi-wavelength demultiplexing in photonic crystal waveguides

“…In the past decades, due to the photonic bandgap (PBG) and the ability to control electromagnetic wave propagation, photonic crystals (PhCs) made from micro-/ nanoscale periodic dielectric materials have been intensively studied and employed to develop novel photonic devices for photonic integrated circuits (PICs) [1][2][3][4][5] . PhC waveguides, formed by introducing a linear defect into a perfect PhC structure, is one of the essential ingredients in PICs.…”