Seminarium MTPR - Prof. UW dr hab. Wiktor Lewandowski

Date, time: November 27, 2024 , 13:00 – 14:00

Abstract:
Thin films exhibiting chiroptical properties hold great potential for emerging photonic technologies relying on the emission or
detection of circularly polarized light. However, further efforts toenhance, tune, and actively regulate thin films' chiroptical activity
are required to fully realize their potential. Recently, we addressedthese challenges by introducing a liquid crystal-assisted method for
fabricating chiroptical thin films [1].

The developed method relies on LCs forming morphologically chiralstructures, such as helical nanofibers, to guide the assembly of
nanoparticles. We have shown that this methodology is universal to Aunanoparticles of different sizes and shapes, Au nanoclusters, perovskitenanocrystals, and other nanoinclusions [2, 3].

Notably, these chiral assemblies exhibit high dissymmetry factors(g-factor on the order of 0.2), which we have proven originates from the
additive molecular and supramolecular chirality [4]. Moreover, thematerials we achieve can respond to thermal and light stimuli [5]. We
recently used these materials to fabricate thin films with a pixelatedstructure, where each pixel exhibits on-demand controlled plasmonic andelectronic handedness [6].

Overall, our approach towards achieving chiral nanomaterials offersadvantages for communication, display, and anticounterfeiting technologies.

References:
[1] Advanced Materials 32, 1904581 (2020).
[2] Advanced Functional Materials 32, 2111280 (2022).
[3] ACS Nano 16, 18472-18482 (2022).
[4] ACS Photonics 11, 4, 1771–1779 (2024).
[5] ACS Nano 17, 6, 5548-5560 (2023).
[6] Advanced Materials 36, 2310197 (2024).