In this letter, we report an all-optical controlled polarization-dependent variable optical attenuator using a photochromic sol gel material developed by us. Optical attenuation is achieved by means of photochromic phase modulation in a Mach-Zehnder interferometric waveguide device fabricated with the sol gel film. A 5-mW/mm2 light illumination at 532 nm on a 3-mm-long sol gel arm was found to produce a complete 2π phase shift between the two arms of the device, resulting in a 15-dB attenuation dynamic range for transverse-electric-polarization light. The response time of the device is around 50 ms. The wavelength-dependent performance of the device has been characterized across the entire C-band.
- All-optical control
- Sol gel
- Variable optical attenuator (VOA)
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Atomic and Molecular Physics, and Optics
- Electronic, Optical and Magnetic Materials