| Aug 20, 2025 |
Chip-based microcombs push nanometer precision in distance measurementA new dual-microcomb method enables chip-scale devices to measure distances with nanometer accuracy, paving the way for advances in nanotechnology and photonics.(Nanowerk News) Optical frequency combs act like extremely precise rulers made of light, allowing scientists to measure time and distance with astonishing accuracy. These tools are vital for technologies that demand measurements at the tiniest scales. |
| Traditional dual-comb ranging methods rely on secondary sampling, which can cause large errors when targets move or when the atmosphere disturbs light paths. This limitation has made it difficult to achieve reliable, real-time measurements in practical situations. |
| To solve this, researchers led by Prof. Zhang Wenfu at the Xi’an Institute of Optics and Precision Mechanics developed a new on-chip cross dual-microcomb (CDMC) method. Instead of relying on two-step sampling, their approach extracts distance information directly in a single measurement, eliminating errors caused by asynchronous sampling. |
| The findings are reported in Science Advances ("Cross dual-microcomb dispersion interferometry ranging"). |
| The team generated two soliton microcombs on a chip using laser-assisted thermal balancing and fine-tuned them for stable operation. The result was a uniform comb structure that allowed one-shot spectral sampling, using either an optical spectrum analyzer or photodetector arrays. |
| Experiments showed extraordinary precision. The system achieved nanometer-level accuracy, with deviations as small as 56 nm over short distances. To extend measurement range while maintaining stability, the researchers introduced microwave injection locking, reducing system jitter and expanding the measurable distance from just millimeters to hundreds of meters. |
| Because the method can be integrated onto a chip, it offers a compact and scalable solution for high-precision distance sensing. This advance has strong implications for nanotechnology, where accurate positioning and alignment at the nanometer scale are critical for developing and testing nanoscale devices and materials. It also strengthens the broader field of nanophotonics, which harnesses light within nanostructured materials for advanced sensing and communication technologies. |
| Source: Chinese Academy of Sciences (Note: Content may be edited for style and length) |
