Orchestrating Polaritonic Crystal Resonances in Transparent Metallic Nanomesh Electrodes.

The development of transparent conductive electrodes (TCEs) is crucial for next-generation optoelectronic devices. In this work, we explore the design of metallic mesh electrodes (MMEs) and fabricate silver MMEs using colloidal lithography, introducing two architectures that operate in different optical regimes: the photonic micromesh (PhoMM) and the plasmonic nanomesh (PlaNM). The PhoMM leverages high electrical conductivity and high optical-window transmission, while the PlaNM exploits plasmonic crystal resonances that enhance the transparency beyond the geometric open-area fraction. A design methodology was developed based on theory, simulation and experimentation, which provides an efficient algorithm for the dimensioning of MMEs with any arbitrary periodic geometry. Through this algorithm, both architectures were dimensioned and fabricated, with PhoMMs achieving Hackee's figure of merit as high as 7.5 × 10-2 Ω-1 and the best PlaNMs as high as 3.8 × 10-3 Ω-1, both surpassing the ITO standard (2.0 × 10-3 Ω-1). This work demonstrates the feasibility of both PhoMMs and PlaNMs, and provides a generic design methodology for the integration of MMEs in a plethora of technologies, such as photovoltaics, light-emitting devices, photodetectors, electrochromic windows, and sensors.