论文标题
由于短暂的声场引起的小球上的声辐射力
Acoustic radiation force on small spheres due to transient acoustic fields
论文作者
论文摘要
声辐射力是在声波作用下物体经历的净力。大多数理论模型都要求声波是周期性的，即使不是纯粹的单频，因此与由于声脉冲引起的声学辐射力无关。在这里，我们介绍了有限的持续性脉冲的概念，这是推导声学辐射力的最一般条件。对于小球，我们将Gor'kov扩展到公式到不稳定的声学场，例如行进的脉冲和干扰波包。在后一种情况下，我们的研究表明，声学对比的概念也与表达声学辐射力有关。对于负造影剂颗粒，声学诱捕区域较短的脉冲变窄，而当脉冲宽度偏离最佳值时，正造影剂（例如生物细胞）可能会落入次级陷阱。这种理论上的见解可能有助于提高脉冲声镊子的选择性。
Acoustic radiation force is a net force experienced by an object under the action of an acoustic wave. Most theoretical models require the acoustic wave to be periodic, if not purely monofrequency, and are therefore irrelevant for the study of acoustic radiation force due to acoustic pulses. Here, we introduce the concept of finite-duration pulses, which is the most general condition to derive the acoustic radiation force. In the case of small spheres, we extend the Gor'kov to formula to unsteady acoustic fields such as traveling pulses and interfering wave packets. In the latter case, our study suggests that the concept of acoustic contrast is also relevant to express the acoustic radiation force. For negative acoustic contrast particles, the acoustic trapping region narrows with shorter pulses, whereas positive contrast particles (such as biological cells) can fall in secondary traps when the pulse width deviates from an optimal value. This theoretical insight may help to improve the selectivity of pulsed acoustic tweezers.
