The Effect of Optical Tweezers

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Mao, Jingjing
Enge, Daniel
Hong, Howie
Rajan, Neil
In this project, we create an optical trap for microscopic polystyrene spheres by constructing optical tweezers using a laser with a wavelength of 532nm. The potential well created by the optical trap is analogous to that of a harmonic oscillator. This allows us to define and measure the stiffness of the trap, which is dependent on the power of the laser. Using the position data obtained by a CCD camera, we can measure the stiffness of the trap using both the equipartition theorem and the mean squared distance method. We measured the trap stiffness for various laser power. Our result shows that the stiffness of the optical trap does not increase linearly with the power of the laser.
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