Enabling infinite Q factors in absorbing optical systems

Radoslaw Kolkowski*, Andriy Shevchenko

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

2 Citations (Scopus)
27 Downloads (Pure)


Resonant optical structures have widespread applications in science and technology. However, their quality (Q) factors can be significantly deteriorated, if some of their parts exhibit optical absorption. Here, we show that by coupling a lossy mode of such a structure to two independent lossless modes, one can create a nonradiating and absorption-free bound state in the continuum (BIC). The Q factor of such a BIC is theoretically unlimited despite interaction with an absorbing structure. We use this mechanism to design a plasmonic metasurface with Q factors that are close to 107 in the visible spectral range. The proposed mechanism is general and can be used to engineer ultrahigh-Q resonances in various systems containing absorbing structures.

Original languageEnglish
Pages (from-to)3443–3454
Issue number17
Publication statusPublished - 1 Aug 2023
MoE publication typeA1 Journal article-refereed


  • bound state in the continuum
  • optical absorption
  • resonant metasurface


Dive into the research topics of 'Enabling infinite Q factors in absorbing optical systems'. Together they form a unique fingerprint.

Cite this