Self-Navigated 3D Acoustic Tweezers in Complex Media Based on Time Reversal
Self-navigated 3D acoustic tweezers. (a) Schematic of self-navigated 3D acoustic tweezers. The freely falling PDMS particle dropped from an arbitrary initial position was tracked by the 3D ultrasonic images at position and the navigation system trapped the particle at . Then, the particle was transferred along a specified path (passing through and ) until it arrived at target position . (b) 3D ultrasonic images monitoring the particle manipulation path in 3D space. (c, d) Optical images monitoring the particle (dyed red) manipulation path in the top view (c) and side view (d). (e) Simulated 3D beam profiles at positions ,,, and . (f, g) Schematic (f) and optical images (g) of manipulating a PS particle in a circular path (10 mm diameter) on the water surface. (h, i) Simulated 3D beam profiles of the vortex acoustic field from the top view (h) and side view (i). The self-navigated 3D acoustic tweezers are shown in Movie S1 and the manipulation of a single PS particle is shown in Movie S2. All scale bars are 10 mm.