Detection of nanoparticles using optical gradient forces
نویسندگان
چکیده
We present a detection scheme for nanoscale particles based on the gradient force and torque near a tightly focused laser beam. The focus affects the path of nanoparticles passing by and a quadrant detector records the particle trajectory. A feedback system continuously adjusts the laser power and thereby prevents the particles from being trapped. Particle size and shape can be assessed by evaluating the time-trace of the quadrant detector signal.
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