Fig. 3: Observation of topological pressure wells at confined edge mode for particle and molecule manipulation.
a, Schematic of topological pressure wells along the edge for particle concentration. The red on the small pillars represents the energy field, and the blue colour gradient around the small pillars indicates topological pressure wells. b, Simulated pressure well and measured time-series observation of 1 µm particle around a small pillar. The yellow arrows represent the 1 µm particle trajectories over time. Scale bar, 10 µm. c, Measured particle velocities of 1 µm polystyrene along a straight interface as a function of excitation frequencies and input voltages. d, Simulated energy fields and measured fluorescence intensity distributions for VPCs without interface and with a Z-shaped interface around the frequency of 23.8 MHz, respectively. Scale bar, 200 µm. e, Measured fluorescence intensity at positions far from (point A), near (points B, C, and D) and without (point E) interface in d. The light-blue region represents the frequency range of the edge state. The data represent the mean ± standard deviation. f, Simulated topological pressure wells (left) and measured fluorescence intensity distribution of 200 nm polystyrene (right) along a straight interface. Scale bar, 20 µm. g, A comparison of simulated energy intensity between topological SAWs and conventional SAWs in solid field. h, Simulated energy fields and measured manipulation of 60 nm polystyrene and DNA molecules at edge-state frequency (33.83 MHz) in a topological device with lattice constant a = 50 µm. Scale bar, 50 µm. The data represent the mean ± standard deviation. i, A comparison of measured fluorescence intensities for concentrated 1 µm polystyrene particles, 60 nm polystyrene particles and DNA molecules using different methods. The experimental data represent the mean ± standard error of the mean from the results of n = 3 DNA samples and polystyrene particles.
