Switchable narrow nonlocal conducting polymer plasmonics

Dongqing Lin; Yulong Duan; Pravallika Bandaru; Pengli Li; Mohammad Shaad Ansari; Alexander Yu Polyakov; Janna Wilhelmsen; Magnus P Jonsson

doi:10.1038/s41467-025-59764-5

Switchable narrow nonlocal conducting polymer plasmonics

Nat Commun. 2025 May 21;16(1):4484. doi: 10.1038/s41467-025-59764-5.

Authors

Dongqing Lin¹, Yulong Duan¹, Pravallika Bandaru¹, Pengli Li¹, Mohammad Shaad Ansari¹, Alexander Yu Polyakov¹, Janna Wilhelmsen¹, Magnus P Jonsson²

Affiliations

¹ Laboratory of Organic Electronics, Department of Science and Technology (ITN), Linköping University, Norrköping, Sweden.
² Laboratory of Organic Electronics, Department of Science and Technology (ITN), Linköping University, Norrköping, Sweden. magnus.jonsson@liu.se.

Abstract

Dynamically switchable surface plasmons in conducting polymers constitute an emerging route towards intelligent metasurfaces, but polymer plasmons have so far suffered from weak resonances with low quality factors (Q < 1-2). Here, we address this by nonlocal coupling of individual poly(3,4-ethylenedioxythiophene) (PEDOT) nanoantennas through collective lattice resonances (CLR) in periodic arrays (with resonance wavelengths around 2.0-4.5 μm). The results show that careful tuning of CLR matching conditions enables organic plasmonic resonances with Q up to 12. Angle-dependent extinction spectra connect the results to the enhancement of radiative coupling from diffractive lattice effects. Furthermore, the nonlocal coupling strength between nanoantenna units and lattice could be modulated via redox reactions, enabling the narrow CLRs to be reversibly switched with large modulation depth (between 7% and 45% extinction). By improving resonance strength and Q, the study circumvents previous limitations of conducting polymer plasmonics and shows feasibility for practical applications in active metasurfaces and nano-optics.