en تخصصي Special Orginal Article <p data-end="1477" data-start="178"></p> <div style="text-align: justify;"><span style="font-size:14px;"><span style="font-family:Times New Roman;">Metamaterials with adjustable effective permittivity and permeability have attracted significant attention in the last decade due to their ability to control electromagnetic propagation and offer unique physical phenomena. This study focuses on epsilon-near-zero (ENZ) materials and their potential applications in overcoming traditional optical limitations such as spherical aberrations. We propose a novel plasmonic ENZ unit cell based on a metal-dielectric metal (Ag-Si3N4-Ag) waveguide configuration specifically designed and optimized for operation at the telecommunication wavelength of 1550 nm. By carefully tailoring the dielectric-to-metal geometric ratio, a graded index (GRIN) metalens is constructed, offering precise phase control. Numerical investigations confirm that the proposed structure achieves a well-defined subwavelength focal spot with negligible phase variation inside the ENZ regime. The study highlights significant advancements in planar lens design, offering a compact, highly efficient solution for subwavelength imaging, optical waveguides, and localized energy transport without chromatic or spherical aberrations. Furthermore, the localized energy squeezing and high transmission efficiency of the proposed structure present promising prospects for environmental health engineering. Specifically, these lenses can be integrated into optofluidic platforms to enhance the sensitivity of optical sensors for the real-time detection of chemical pollutants and emerging pharmaceutical contaminants in wastewater.</span></span><div style="text-align: justify;"></div></div> Epsilon-Near-Zero (ENZ) materials, Plasmonic metalens, Metamaterials, Graded-index lens, Optical waveguides, Optofluidic sensors, Localized Surface Plasmon Resonance (LSPR), Environmental monitoring. 38 47 http://jrhms.thums.ac.ir/browse.php?a_code=A-10-186-8&slc_lang=en&sid=1 Hamid Reza Sobhi 10031947532846002245 10031947532846002245 Yes Department of Chemistry, Payame Noor University, Tehran, Iran Mojtaba Yeganeh 10031947532846002246 10031947532846002246 No Research Center for Environmental Health Technology, Iran University of Medical Sciences, Tehran, Iran Ali Habibi 10031947532846002247 10031947532846002247 No Research Center for Environmental Health Technology, Iran University of Medical Sciences, Tehran, Iran