2025/03/26 by Jayita Dutta, Antonio Ferraro, Dutta, Jayita +13
Engineering · Materials Science · #Advanced Fiber Optic Sensors #FOS: Physical sciences #Liquid Crystal Research Advancements #Optics (physics.optics) #Photonic and Optical Devices
paper · pdf · doi:10.48550/arxiv.2503.21012
openalex publication_date 2025/03/26 · openalex created_date 2025/10/11 · openalex updated_date 2026/07/28
The development of compact, low-power, and high-performance integrated photonic phase shifters is critical for advancing emerging technologies such as light detection and ranging (LiDAR), optical information processing and quantum applications. Liquid crystal (LC)-based phase shifters offer a promising solution thanks to their large refractive index contrast and their low power consumption. However, it remains challenging to incorporate LCs into integrated photonics and the operating wavelength has been limited to near infrared. Here, we demonstrate a liquid-crystal-based phase shifter operating at 780 nm, a relevant wavelength for cold atom-based quantum applications, by incorporating nematic LCs (E7) into a silicon nitride (SiN) ring resonator. Our device achieves 2pi phase modulation with very low power of 2.1 nW and low driving voltages of 7 V with exceptionally low Vpi times L (half wave voltage times length) value of 0.014 V-cm, enabling precise control over light propagation in a compact footprint. This work marks a significant step toward realizing low-power, compact, and efficient LC integrated photonic circuits based on SiN platform for next-generation LiDAR and quantum optical systems.