Microfiber knot resonator with 10<sup>7</sup> Q-factor record

Xinxin Zhou; Zixuan Ding; Fei Xu

doi:10.1038/s41377-025-02124-1

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Microfiber knot resonator with 10⁷ Q-factor record

Original Articles

- Microfiber knot resonator with 10⁷ Q-factor record
- Light: Science & Applications Vol. 15, Issue 5, Pages: 1639-1651(2026)
- Affiliations：
  
  1.National Laboratory of Solid-State Microstructures and College of Engineering and Applied Sciences, Nanjing University, Nanjing 210023, China
  2.Shenzhen Research Institute of Nanjing University, Shenzhen 581000, China
- Author bio：
  
  Fei Xu (feixu@nju.edu.cn)
- Funds：
- DOI：10.1038/s41377-025-02124-1
  CLC：
- Received：10 March 2025，
  
  Revised：2025-11-03，
  
  Accepted：06 November 2025，
  
  Online First：06 March 2026，
  
  Published：31 May 2026
- Accepted：
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Zhou, X. X., Ding, Z. X. & Xu, F. Microfiber knot resonator with 10⁷ Q-factor record. Light: Science & Applications, 15, 1639-1651 (2026). DOI: 10.1038/s41377-025-02124-1.
DOI：

Zhou, X. X., Ding, Z. X. & Xu, F. Microfiber knot resonator with 10⁷ Q-factor record. Light: Science & Applications, 15, 1639-1651 (2026). DOI: 10.1038/s41377-025-02124-1. DOI：

摘要

Abstract

Despite the realization of ultra-high-quality-factor (UHQ) in various dielectric micro-resonators with extensive applications

UHQ microfiber resonators which are directly compatible with all-fiber framework have not yet been achieved

primarily because of the insufficient research on the mechanical properties of microfibers

and the challenges of coupling regulation. Here

we constructed an UHQ microfiber knot resonator (MKR) fabrication model

addressing the decades-long Q-factor bottleneck and achieving a record Q-factor of 3.9 × 10

which is an improvement of three orders of magnitude compared to conventional levels. By controlling environmental parameters for producing high-quality microfibers with uniform stress and low loss

along with experimental and theoretical investigation in coupling mechanism

optimized conditions are attained

offering experimental guidance for fabricating UHQ-MKR stably and reproducibly. After fabrication and characterization

the UHQ-MKR device is also applied into an all-fiber laser scheme to boost narrow-linewidth single-frequency laser operation

highlighting the potential of the resonator. The research opens an era of UHQ microfiber resonator exceeding 10

level

paving the path for more precision and efficient microfiber guiding-wave photonics.

关键词

Keywords

references

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Microfiber knot resonator with 107 Q-factor record

DOI：10.1038/s41377-025-02124-1

摘要

Abstract

关键词

Keywords

references

Microfiber knot resonator with 10⁷ Q-factor record