Mid-air acoustic levitation is becoming a powerful tool to suspend and manipulate millimetric objects. Because of its unique characteristics, acoustic levitation is suitable to trap a wide variety of materials such as liquids, solids, soap bubbles, and even living creatures. Acoustic levitation can also be combined with noncontact measurement systems, allowing contactless analysis and characterization of levitating samples. In this article, we review some of the advances that have been made over the last decade. We also present the technical challenges that must be overcome in order to extend the capability of current acoustic levitation devices and, finally, we point out future directions for acoustic levitation.

中文翻译：

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空中声悬浮：最新进展、挑战和未来展望

空中声悬浮正在成为悬浮和操纵毫米级物体的强大工具。由于其独特的特性，声悬浮适用于捕获各种材料，例如液体、固体、肥皂泡，甚至是生物。声悬浮还可以与非接触式测量系统相结合，从而对悬浮样品进行非接触式分析和表征。在本文中，我们回顾了过去十年中取得的一些进展。我们还提出了必须克服的技术挑战，以扩展当前声悬浮设备的能力，最后，我们指出声悬浮的未来方向。