Topological acoustics has recently revolutionized fundamental concepts of acoustic propagation, giving rise to strikingly unique acoustic edge modes immune to backscattering. Despite the rapid progress in this field, simultaneous realization of reconfigurability, intelligentization, and automatic control over acoustic propagation paths is posing a great challenge. This challenge is overcome by proposing the concept of a programmable acoustic topological insulator based on two digital elements “0” or “1,” which consist of honeycomb‐lattice sonic crystals made of cylindrical rods with different diameters. The acoustic propagation paths in the topological insulators can be controlled automatically by programming different coding sequences, which arises from efficient transformation of pseudospin‐dependent edge modes on both interfaces of the digital elements. More importantly, a unique unit is experimentally fabricated that has either a “0” or “1” response automatically manipulated by an air cylinder, and design topological insulators with programmable functionality, to realize three digital acoustic devices, such as a single‐pole double‐throw switch, a single‐pole single‐throw switch, and a tunable logic gate. The proposed programmable topological insulators may enable future intelligent acoustic devices with exciting reconfigurable and programmable functionalities, which may lead to important advances in various applications, such as integrated acoustics, acoustic security, and information processing.

We report both experimentally and numerically that a broadband acoustic lens with asymmetric focusing is realized by dual-layer metasurfaces in air. The acoustic waves can be focused on a side with 0.4 wavelength resolution focusing characteristic, but cannot transmit through the lens in a large range of incident angles on the other side. This exotic phenomenon exists in the range of 2910–3610 Hz, which arises from the asymmetric phase manipulation induced from the dual-layer metasurfaces. More importantly, without changing the structure of both metasurfaces, the horizontal and vertical positions of the focus can be systematically manipulated by mechanically changing the distance between both metasurfaces and the incident angle, respectively. The proposed lens has the advantages of broadband multifunctionality, subwavelength focusing, planar structure, and tunable properties, showing promising applications in focused ultrasound therapy and medical ultrasound imaging.

A disposable acoustofluidic platform was developed for nano/microparticle separation with high versatility, precision, and biocompatibility.

Three-dimensional (3D) gapless topological phases can be classified by the dimensionality of the band degeneracies, including zero-dimensional (0D) nodal points, one-dimensional (1D) nodal lines, and two-dimensional (2D) nodal surfaces. Both nodal points and nodal lines have been realized recently in photonics and acoustics. However, a nodal surface has never been observed in any classical-wave system. Here, we report on the experimental observation of a twofold symmetry-enforced nodal surface in a 3D chiral acoustic crystal. In particular, the demonstrated nodal surface carries a topological charge of 2, constituting the first realization of a higher-dimensional topologically-charged band degeneracy. Using direct acoustic field measurements, we observe the projected nodal surface and its Fermi-arc-like surface states and demonstrate topologically-induced robustness of the surface states against disorders. This discovery of a higher-dimensional topologically-charged band degeneracy paves the way toward further explorations of the physics and applications of new topological semimetal phases.

Efficient isolation and analysis of exosomal biomarkers hold transformative potential in biomedical applications. However, current methods are prone to contamination and require costly consumables, expensive equipment, and skilled personnel. Here, we introduce an innovative spaceship-like disc that allows Acoustic Separation and Concentration of Exosomes and Nucleotide Detection: ASCENDx. We created ASCENDx to use acoustically driven disc rotation on a spinning droplet to generate swift separation and concentration of exosomes from patient plasma samples. Integrated plasmonic nanostars on the ASCENDx disc enable label-free detection of enriched exosomes via surface-enhanced Raman scattering. Direct detection of circulating exosomal microRNA biomarkers from patient plasma samples by the ASCENDx platform facilitated a diagnostic assay for colorectal cancer with 95.8% sensitivity and 100% specificity. ASCENDx overcomes existing limitations in exosome-based molecular diagnostics and holds a powerful position for future biomedical research, precision medicine, and point-of-care medical diagnostics.