The missing link between standing- and traveling-wave resonators

Qi Zhong, Haoqi Zhao, Liang Feng, Kurt Busch, Şahin K. Özdemir, Ramy El-Ganainy

Research output: Contribution to journalArticlepeer-review


Optical resonators are structures that utilize wave interference and feedback to confine light in all three dimensions. Depending on the feedback mechanism, resonators can support either standing- or traveling-wave modes. Over the years, the distinction between these two different types of modes has become so prevalent that nowadays it is one of the main characteristics for classifying optical resonators. Here, we show that an intermediate link between these two rather different groups exists. In particular, we introduce a new class of photonic resonators that supports a hybrid optical mode, i.e. at one location along the resonator the electromagnetic fields associated with the mode feature a purely standing-wave pattern, while at a different location, the fields of the same mode represent a pure traveling wave. The proposed concept is general and can be implemented using chip-scale photonics as well as free-space optics. Moreover, it can be extended to other wave phenomena such as microwaves and acoustics.

Original languageEnglish (US)
Pages (from-to)4427-4437
Number of pages11
Issue number19
StatePublished - Sep 2022

All Science Journal Classification (ASJC) codes

  • Biotechnology
  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Electrical and Electronic Engineering


Dive into the research topics of 'The missing link between standing- and traveling-wave resonators'. Together they form a unique fingerprint.

Cite this