Optically assisted loading of single micro-diamonds in a Stylus trap under ambient conditions

The controlled trapping of micro- to submicrometer-sized particles is crucial for fundamental research, precision metrology, and applied technologies. However, existing loading methods often rely on stochastic processes, leading to low reproducibility and limited scalability. Here, we present an optically assisted deterministic loading method for integrating charged micro- and submicrometer particles into a so-called Stylus trap with high-optical access under ambient conditions. A focused laser beam dislodges particles from a reservoir, guiding them into the trap via radiation pressure, electrostatic forces, and background air collisions. By optimizing key parameters, we achieve 95−6+2 % loading efficiency and near-linear control over the number of trapped particles. Our scalable and reproducible approach enables precise particle manipulation, bridging atomic physics techniques with applications in quantum technology, nano-mechanics, and sensing. Future developments will focus on extending the method to vacuum environments and refining charge control mechanisms for enhanced selectivity.