Bridging the gap between optical fibers and silicon photonic integrated circuits

Abstract

We present a rigorous approach for designing a highly efficient coupling between single mode optical fibers and silicon nanophotonic waveguides based on diffractive gratings. The structures are fabricated on standard SOI wafers in a cost-effective CMOS process flow. The measured coupling efficiency reaches -1.08 dB and a record value of -0.62 dB in the 1550 nm telecommunication window using a uniform and a nonuniform grating, respectively, with a 1 dB-bandwidth larger than 40 nm.

In- and out-coupling devices for subwavelength waveguides. Part 2

“…The maximal observed CE was about 70% [22]. The grating of a more complicated profile than lines with a constant period (apodized gratings) demonstrated theoretically and experimentally CE up to 87% [23].…”

“…Максимальный продемон-стрированный коэффициент ввода составил около 70% [22]. Решетки более сложного профиля, нежели линии с равным периодом (аподизиро-ванные решетки), продемонстрировали теорети-чески и экспериментально коэффициент ввода до 87% [23].…”

Hybrid dielectric waveguide spectroscopy of individual plasmonic nanoparticles

“…Higher coupling efficiencies could be attained by incorporating a metal reflector underneath the silicon nitride coupler embedded in the silica buffer layer 26 or shaping the grating appropriately. [27][28][29] Notwithstanding, the configuration still allows a broadband performance in the spectral region that is of practical importance for plasmonics -i.e. 550 -800 nm.…”

“…In principle further improvement may be achieved by optimizing grating couplers. [27][28][29]31 We now turn the attention to coupling between plasmonic nanoparticles and waveguides (see Fig. 3).…”

Single waveguide silicon-organic hybrid modulator

“…the waveguide loss for the fundamental TE mode in a 400 nm wide passivated waveguide is reduced from more than 10 to 3.3 dB cm −1 in the technology used up to date. The coupling efficiency of the grating couplers can be enhanced by an aperiodic grating design with back side reflector in the used technology to −0.62 dB (Sfar Zaoui et al, 2014). To achieve a balanced excitation of the two TE modes, an additional lateral fiber offset with respect to the center of the grating coupler is necessary (Hoppe et al, 2015).…”