Broadband isotropic μ-near-zero metamaterials

Natural diamagnetism, while being a common phenomenon, is limited to permeability values close to unity. Artificial diamagnetics, to the contrary, can be engineered to provide much lower values and may even possess an effective permeability close to zero. In this letter, we provide an experimental confirmation of the possibility to obtain extremely low permeability values by manufacturing an isotropic metamaterial composed of conducting cubes. We show that the practical assembly is quite sensitive to fabrication tolerances and demonstrate that permeability of about μ=0.15 is realisable.This work was supported by the Ministry of Education and Science of Russian Federation (Project 11.G34.31.0020), Dynasty Foundation (Russia), grant of the President of Russian Federation, and by the Australian Research Council (CUDOS Centre of Excellence CE110001018)