ABSTRACT
We demonstrate a robust 3-dB directional coupler which has a narrow silicon wire core and a wide gap. Sensitivity to the gap variation is decreased to one tenth that of a conventional directional coupler. Better spectral stability due to the enhanced robustness to waveguide geometrical fluctuations was experimentally verified.
ABSTRACT
n-channel body-tied partially depleted metal-oxide-semiconductor field-effect transistors (MOSFETs) were fabricated for large current applications on a silicon-on-insulator wafer with photonics-oriented specifications. The MOSFET can drive an electrical current as large as 20 mA. We monolithically integrated this MOSFET with a 2 × 2 Mach-Zehnder interferometer optical switch having thermo-optic phase shifters. The static and dynamic performances of the integrated device are experimentally evaluated.
Subject(s)
Interferometry/instrumentation , Refractometry/instrumentation , Signal Processing, Computer-Assisted/instrumentation , Silicon/chemistry , Transistors, Electronic , Electric Conductivity , Equipment Design , Equipment Failure Analysis , Hot Temperature , Photons , Systems IntegrationABSTRACT
The authors report their latest results on II-VI intersubband all-optical switches in which the 10 dB absorption saturation energy is lowered to ~2.0-2.2 pJ for 1.55-1.58 mum by decreasing the thickness of the active layer and increasing the refractive index difference between the core layer and the cladding layers in waveguides. Such low saturation energies greatly improve the switching performance. <7 pJ pump energy at 1520 nm is sufficient for realizing 10 dB switching operation at 1566 nm (switching energy: ~0.7 pJ/dB). To the best of our knowledge, these switching energy and saturation energy values are the lowest reported ones for such ultrafast intersubband all-optical switches at telecommunication wavelengths.