Antman meets The Flash: Nano microscopy faster than a cycle of light

Nanotechnology holds exceptional promise in a huge variety of applications, from electronics and solar cells to medical nanobots. Such nanodevices are clearly very small. In fact, their characteristic length scale is included in their name: 1-100 nanometers, the crossover region between quantum mechanical and classical behavior. But did you know that the processes that occur on the nanoscale are also very fast? For example, collective oscillations of mobile electrons and atomic lattice vibrations both occur on a time scale of 10-14 - 10-12 seconds. Meanwhile, transient states of matter typically survive for less than 10-10 seconds.

The evolution of these dynamics can be captured stroboscopically using ultrashort pulses of laser light. Unfortunately, conventional ultrafast experiments generally measure only macroscopic averages, since diffraction prevents laser pulses from being focused down to the nanoscale. In this talk, I will describe how a sharp metal needle can be used to confine light to a volume much smaller than its free space wavelength. This has allowed us to observe material dynamics inside single nanoparticles, watch light oscillate on the nanoscale, and track the ultrafast motion of a single molecule for the first time.

Tyler Cocker — Department of Physics, University of Regensburg
Thursday 18 May 2017, 12:00
Location: C4.174