Integrated visible-light liquid-crystal-based phase modulators

• Main Authors: Notaros, Milica (Author), Dyer, Thomas (Author), Raval, Manan (Author), Baiocco, Christopher (Author), Notaros, Jelena (Author), Watts, Michael R (Author)
• Format: Article
• Language: English
• Published: Optica Publishing Group, 2022-07-15T17:15:18Z.
• Subjects: Article
• Online Access: Get fulltext

In this work, an integrated liquid-crystal-based phase modulator operating at visible wavelengths was developed and experimentally demonstrated. A visible-light silicon-nitride-based 300-mm-wafer foundry platform and a liquid-crystal integration process were developed to leverage the birefringence of liquid crystal to actively tune the effective index of a section of silicon-nitride waveguide and induce a phase shift over its length. The device was experimentally shown to achieve a 41π phase shift within 4.8 Vpp for a 500-µm-long modulator, which means that a 2π phase shifter would need to be only 24.4 µm long. This device is a compact and low-power solution to the challenge of integrated phase modulation in silicon nitride and paves the way for future low-power small-form-factor integrated systems at visible wavelengths.