Two-dimensional nanoultrasonic imaging by using acoustic nanowaves

Two-dimensional ultrasonic imaging is demonstrated by using acoustic nanowaves. With a 14nm acoustic wavelength, both axial and transverse resolutions of a few tens of nanometers are thus achieved. This ultrasonic-based nondestructive technique not only images but also reconstructs the subsurface nanostructures including the depth positions of the buried interfaces. By demonstrating two-dimensional nanoultrasonic scans in depth and transverse (or z-x) axes, we show that acoustic nanowaves can be a promising tool for future subsurface three-dimensional noninvasive imaging with nanometer resolutions.