Ferrohydrodynamic pumps, with their compact design, offer a practical and efficient alternative to traditional pneumatic or mechanical pumps for driving microfluidic channels and fluidic devices, eliminating mechanical vibrations. A novel self‐circulating ferrohydrodynamic system has been developed to remotely control fluid flow within a linear acoustic cavity using a laser‐induced photothermal temperature gradient. This system enables the modulation of fluid flow rates in compact channels through adjustments in a D.C. magnetic field or laser‐induced surface temperature changes. Notably, laser intensity can accelerate, decelerate, or reverse flow rates within the channel, influencing ultrasonic waves propagating through fluidic cavities designed to resonate between 500 kHz and 700 kHz. The dynamic nature of the magnetoactive fluid cavity enhances wave‐matter interactions, particularly in acoustic domains. Laser‐induced flow control allows for precise manipulation of ultrasonic wave characteristics such as frequency, amplitude, mode splitting, phase shifting, and unidirectional transmission. This capability also supports the optical regulation of acoustic energy flow rates by halting or reversing fluid motion within the cavity. These advancements hold significant potential for applications in cavity acoustodynamics and underwater signal processing, promising innovations in remote fluidic control and acoustic modulation technologies.

中文翻译：

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用于调制超声波的激光控制铁流体动力学流体腔


铁磁流体动力泵凭借其紧凑的设计，为传统气动或机械泵提供了实用且高效的替代方案，用于驱动微流体通道和流体装置，消除机械振动。一种新型自循环铁水动力系统已被开发出来，可以利用激光诱导的光热温度梯度远程控制线性声腔内的流体流动。该系统可以通过调节直流磁场或激光引起的表面温度变化来调节紧凑通道中的流体流速。值得注意的是，激光强度可以加速、减速或逆转通道内的流速，从而影响通过设计用于在 500 kHz 至 700 kHz 之间共振的流体腔传播的超声波。磁活性流体腔的动态性质增强了波与物质的相互作用，特别是在声学领域。激光诱导的流量控制可以精确操纵超声波特性，例如频率、幅度、模式分裂、相移和单向传输。该功能还支持通过停止或反转腔内的流体运动来光学调节声能流速。这些进步在腔声动力学和水下信号处理方面具有巨大的应用潜力，有望在远程流体控制和声调制技术方面实现创新。