Optical torque wrench: Angular trapping, rotation, and torque detection of quartz microparticles
Optical torque wrench: Angular trapping, rotation, and torque detection of quartz microparticles
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DOI：
10.1103/physrevlett.92.190801
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发表时间：
2004-05-14
影响因子：
8.6
通讯作者：
Wang, MD
中科院分区：
文献类型：
--
作者：
La Porta, A;Wang, MD
我们描述了一种可以测量施加在角捕获的石英颗粒上的瞬时角位移和扭矩的装置。扭矩是通过检测发射阱光束角动量的变化来测量的。捕获粒子的旋转布朗运动及其功率谱密度用于确定角捕获刚度。该装置的特点是一个反馈控制夹紧扭矩或其他旋转量。所展示的扭矩灵敏度是研究已知生物分子马达的理想选择。
We describe an apparatus that can measure the instantaneous angular displacement and torque applied to a quartz particle which is angularly trapped. Torque is measured by detecting the change in angular momentum of the transmitted trap beam. The rotational Brownian motion of the trapped particle and its power spectral density are used to determine the angular trap stiffness. The apparatus features a feedback control that clamps torque or other rotational quantities. The torque sensitivity demonstrated is ideal for the study of known biological molecular motors.