Related Experiment Video
Updated: Jun 18, 2025

Optical Trap Loading of Dielectric Microparticles In Air
Published on: February 5, 2017
Impedance matching in optically induced dielectrophoresis: Effect of medium conductivity on trapping force
Mohammad Asif Zaman1, Mo Wu1, Wei Ren1
1Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA.
Abstract:
An impedance analysis for optically induced dielectrophoresis is presented. A circuit model is developed for this purpose. The model parameters are fully defined in terms of the geometrical and material properties of the system. It is shown that trapping force can only be generated when the material properties follow certain impedance matching conditions. The impedance match factor is introduced to succinctly quantify the phenomenon. It is used to calculate bounds on the allowed electrical conductivity of the suspension medium. Results from the proposed model are found to be in good agreement with full-wave numerical simulations. By computing the acceptable set of material parameters with little computational cost, the presented analysis can streamline ODEP system design for various applications.
Related Concept Videos
Susceptibility, Permittivity and Dielectric Constant
Dielectric Polarization in a Capacitor
Electrostatic Boundary Conditions in Dielectrics
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's...

