Phys.org  March 6, 2024 Zero-index metamaterials (ZIMs) can support uniform electromagnetic field distributions at any frequency, but their applications are hampered by the ZIM’s homogenization level—only 3-unit cells per free-space wavelength, which is fundamentally limited by the low-permittivity inclusions and background matrix. An international team of researchers (USA – Stanford University, China) demonstrated a highly homogeneous microwave ZIM with an over threefold increase in the homogenization level by filling high-permittivity SrTiO3 ceramic pillars in BaTiO3 background matrix. They achieved an antenna, and a concave lens with a focal length of as short as 1λ0… read more. Open Access TECHNICAL ARTICLE