Ultralow-power optical trapping improves stability of molecular graphene quantum dots, suggesting new applications in biocompatibility.
Precise positioning of quantum emitters is essential for next‐generation photonic technologies, yet conventional free‐space optical trapping methods require high laser powers that damage sensitive nanoparticles through heating. Here, ultralow‐power trapping of biocompatible molecular graphene quantum dots (GQDs) is demonstrated using metamaterial plasmonic tweezers, achieving record‐high normalized trap stiffness values of 8.8 (fN nm −1 ) (mW/µm 2 ) −1 at intensities below 1 mW/µm 2 . Custom 19‐nm molecular GQDs containing twisted double[7]carbohelicene (D7H) molecular cores are synthesized and their trapping dynamics are systematically investigated across dual hotspot types in the metamaterial array. A critical thermal threshold is identified at incident intensity ≈1.5 mW µm −2 corresponding to 72 °C temperature rise in the solution where plasmonic heating generates convective flows that compete against the optical trapping forces, dramatically reducing trap stability. The results establish safe operating regimes for heat‐sensitive quantum emitters and reveal the fundamental interplay between optical and thermal forces in plasmonic trapping systems. This platform enables efficient nanopositioning of quantum emitters in ordered arrays while maintaining biocompatibility and photostability, opening pathways toward scalable single‐photon source architectures and bioimaging applications.
No takes yet. Share an insight, caveat, or question.
Bouloumis et al. (2025) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: