Electronic devices emit electromagnetic (EM) waves, which may interfere with neighboring electronic components, a phenomenon known as electromagnetic interference (EMI). Conventional metallic shields exhibit high shielding effectiveness values. Yet, most of the power is reflected, resulting in secondary EM pollution. Instead, one can make use of polymer nanocomposite shields which are able to partially absorb the incident power.
The challenge is to produce polymer-based shields of high shielding effectiveness where most of the power is absorbed instead of reflected. In this work, we explore the use of 3D gradients in electromagnetic properties within a nanocomposite layer to fill this gap in material property space. An efficient 3D finite element model is constructed to predict the shielding performance as a function of EM property gradient and geometric design of the layer. After validation with experimental data for uniform nanocomposite layers, we use the model to identify optimal material design cases.