Optical Trapping and Two-Photon Excitation of Colloidal Quantum Dots using Bowtie Apertures

Russell A. Jensen, I-Chun Huang, Ou Chen, Jennifer T Choy, Thomas S. Bischof, Marko Loncar, and Moungi G. Bawendi

We demonstrate bowtie apertures that were designed and fabricated by a lift-off process to optically trap individual, 30 nm silica coated quantum dots (scQD). Simulations and experiments confirm the trapping capability of the system with a relatively low continuous wave trapping flux of 1.56 MW/cm2 at 1064 nm. Additionally, the scQD emits upon trapping via two-photon excitation from the trapping laser due to strong field enhancement inside the aperture. This system is an exciting platform for studying light-matter interactions and mulitphoton processes in single emitters.

DOI