Hybrid metalens for ultrawide-angle and high-efficiency focusing of waterborne sound
Phys. Rev. Applied 24, 064054 – Published 19 December, 2025
DOI: https://doi.org/10.1103/d7kq-cl68
Abstract
Acoustic metalenses that enable wide-incident-angle and high-efficiency focusing are in high demand for diverse applications, from underwater imaging to biomedical diagnostics. In this work, we introduce a design paradigm for an acoustic metalenses based on a quadratic phase profile, which can incorporate a synergistic combination of a central metasurface and a peripheral metagrating. By our integrating grating diffraction theory with phase engineering and applying an intelligent optimization algorithm, our design achieves high-efficiency, ultrawide-angle focusing of underwater sound across a continuous angular range from 0° to ±85°, with an average efficiency of 31.72%. Thanks to its wavelength-scale thickness and distinct design principle, this metalens provides a compact platform suitable for integration into advanced acoustic systems with complex functional requirements.
