Real-Time 3D Single-Particle Tracking: Spectroscopy, Imaging, and Control
Haw Yang

Real-time 3D single-particle tracking spectroscopy is an experimental technique that allows one to follow a nanoprobe as its moves in three-dimensional space, either by diffusion or by active locomotion. The technique keeps the nanoprobe at the center of the focus at all times by moving the sample stage to counter any movements that the probe exhibits. Effectively, the apparatus transforms the experimental coordinate from lab-based from to probe-based frame. This way, it would become possible to do time-dependent experiments on the probe or the molecule tethered to the probe as if the particle or molecules are immobilized. This presentation will discuss its principles, capabilities, and applications—including (1) 3D multi-resolution imaging of individual virus-like nano particles interacting with a live cell, (2) temperature-jump experiments for testing hot-Brownian theory, and (3) steering of self-propelled micro-swimmers and its implications in bacterial locomotion.