This tutorial offers a concise yet rigorous overview of acoustic tweezer technologies, emphasizing the governing physical principles. We first introduce acoustic wave propagation in fluids and solids and explain how momentum transfer from acoustic fields produces time-averaged acoustic radiation forces and torques. Using intuitive energy-landscape descriptions (e.g., Gor’kov potential), we describe stable trapping in standing- and traveling-wave fields, the formation of pressure/velocity nodes and antinodes, and how particle size, density, and compressibility determine selectivity and trapping strength.
Building on these fundamentals, we summarize key design strategies, including transducer configurations, material choices, and system architectures for generating controllable trapping patterns. We then review practical fabrication and integration workflows for ultrasound transducers, along with alignment and co-registration with optical microscopy for visualization and quantification. Finally, we survey representative applications ranging from single-cell manipulation and micro-assembly to biomechanical characterization, illustrating the technology’s impact on biomedical research and emerging diagnostic workflows. Overall, this tutorial links first-principles physics to device realization and application-driven implementation.
