Nonlinear Response of Nanoparticles to Optical Tweezers Electrophoresis

Abstract

In physics, the optical trap has a wide range of uses. It can for example be used trap a cloud of particles. ”Low” density clouds have been used to create more sensitive interferometers, while ”high” density clouds are used to create Bose-Einstein condensates. In this project however, the optical trap isn’t used to trap a cloud of particles, but instead it’s used to trap a singular nanoparticle. Once such a nanoparticle has been trapped, I want to subject it to a high frequency alternating electric field and study the particles response to this field in time. Before I can start applying a high frequency alternating electric field, I first want to check for the expected behavior to different electric fields of which one knows what the response should be. These electric fields lie within the low and middle frequency regime. When both symmetric and asymmetric electric fields within the low frequency regime (f < 10000 Hz) are applied, the results for the measured ingoing electric field and the response of the nanoparticles are similar. However, when the mid frequency regime (10000 Hz < f < 250000 Hz) is reached, the measured ingoing electric field and the response of the nanoparticles start showing different results.