Subwavelength Ultrasonic Imaging with Harmonic Resonant Tunneling Metasurface

This paper presents a novel approach to achieve subwavelength ultrasonic imaging using a harmonic resonant tunneling metasurface. By exploiting the nonlinear properties of the metasurface, we demonstrate the capability of generating higher-order harmonics that can be used to overcome the diffraction limit of conventional ultrasonic imaging techniques. This method allows for the visualization of fine details beyond the wavelength of the incident ultrasonic wave, opening up new possibilities for high-resolution imaging in various fields such as medical diagnostics and non-destructive testing.