The Institute of Photonics Technologies at Aston University in the UK recently published research results in the journal Optics, developing a novel tunable optical micro-resonator. This device forms a resonant cavity at the intersection of crossed optical fibers, providing innovative solutions for photonic integrated circuits and precision sensors.

Led by Professor Misha Sumetsky, the research team discovered that when two optical fibers cross at a specific angle, van der Waals forces can form an optical resonator with a high quality factor (Q value of approximately 2×10^6). "This geometric structure opens new doors for miniaturized, tunable photonic systems," said Professor Sumetsky. The design overcomes the limitations of traditional monolithic micro-resonators, enabling picometer-level spectral tuning by simply adjusting the fiber crossing angle.

Experiments showed that rotating the fiber by a fraction of a degree can alter the resonator's free spectral range while maintaining high Q-value characteristics. The researchers noted that the Q value could potentially reach the order of 10^8 in cleaner environments. The technology is based on the Surface Nanoscale Axial Photonics (SNAP) platform, with theoretical modeling closely aligning with experimental results.

"The system is highly suitable for micro-electro-mechanical system integration, enabling precise spectral control," Professor Sumetsky added. This innovation holds potential applications in quantum information processing, low-repetition-rate optical frequency comb generation, and nonlocal sensing, providing new ideas for the development of next-generation photonic devices.