Diamagnetic levitation presents a promising platform for realizing resonant sensors and energy harvesters. The technique offers mechanical isolation from the environment while operating with zero power consumption. This unique feature ensures exceptional sensitivity and accuracy in numerous applications. However, the presence of eddy currents in the levitating plate, induced by the alternating magnetic field, poses challenges, leading to increased damping and subsequently limiting the performance of levitating resonators. To address these issues, this study proposes a novel solution through the segmentation of diamagnetic plates. By dividing a pyrolytic graphite plate into smaller blocks, the flow of eddy currents is effectively restricted, resulting in reduced damping and significantly higher Q factors. By comparing the theoretical predictions using a FEM model from an earlier study with the measurements conducted the proposed technique is further validated. This comparative analysis demonstrates the effectiveness of the segmentation approach in mitigating damping due to eddy currents. Furthermore, the implementation of the proposed method led to remarkable results, with achieved Q factors exceeding 150 thousand.

Over the past decades the diamagnetic effect has been used for a variety of applications. This ranges from levitating a living frog to stabilizing a force sensor, designing an acceleration sensor and determin­ing the power of a laser. Diamagnetic levitation is the only method in which a passive stable levitation of an object can be achieved. Such a stable levitation has the benefits that the levitated object is iso­lated from its environment, thus eliminating mechanical damping and friction. Furthermore, no energy or control mechanisms are needed to sustain the levitation and to keep the object in its place. With the decrease in the damping, due to the elimination of the mechanical damping component, potential non­linearities in the movement of the plate can present themselves. Such nonlinearities can be exploited in, for example, energy harvesters. In such energy harvesters, the nonlinearities can be used to increase the range of frequencies at which energy can be harvested. As both diamagnetism and nonlineari­ties have their benefits, this study aims at investigating the nonlinear behaviour of a diamagnetically levitating plate in the vertical direction. An analytical model has been constructed which aimed at pre­dicting the (non)linear behaviour of a pyrolytic graphite plate, levitating over a 2x2 array of permanent magnets, which is actuated electrostatically. The model is verified numerically using COMSOL and has been used to predict both the static -­ and dynamic behaviour of the plate. Experiments have been conducted to assess the validity of the analytical predictions. It is found that the static behaviour and the linear dynamic behaviour of the plate can be predicted analytically within certain margins. The ana­lytical model indicates that all combinations of the magnetic force and electrostatic forces investigated have a softening effect on the levitating plate. A softening response is also observed in experiments. However, the analytical model cannot perfectly predict the experimental frequency response functions. A possible reasons for this discrepancy might be mode coupling. Overall, the study of the nonlinear dynamics for a diamagnetically levitating plate will help to gain more understanding on its fundamental mechanism and thus pave a way for its wider applications.