In this talk, we will explore some recent results in observations of structure and dynamics in a variety of systems ranging from polymer dynamics in ambient conditions, 3D atomic resolution mapping of the structure of the solid-liquid interface, defect dynamics in crystal lattice and biologically relevant materials and molecules in fluid. In particular, dynamics can now be captured at frame rates ranging from >1,000 seconds/image to <100 milliseconds/image.
Describes unconventional use of conventional techniques (SAD,CBED, HREM and Fourier analysis) to elucidate hard-to-access structural information at the nano scale.
The frontier in solar energy research now lies in learning how to integrate functional entities across multiple length scales to create optimal devices. Advancing the field requires transformative experimental tools that probe energy and charge transfer processes from the nano to the meso length scales. This talk discusses ultrafast microscopy as a new means to visualize exciton and charge transport in solar cell materials.
We have developed transient absorption microscopy (TAM) with a time resolution of ~ 200 fs and ~ 50 nm spatial precision to directly visualize hot carrier propagating in hybrid organic-inorganic perovskite (CH3NH3PbI3) thin films and single crystals. Three distinctive transport regimes are observed. 1) quasiballistic transport, 2) nonequilibrium transport, and 3) diffusive transport. The nonequilibrium transport persisted over tens of picoseconds and ~ 600 nanometers before reaching the diffusive transport limit. These results suggest a potential for hot carrier based devices, in which the Shockley-Queisser limit could be overcome.
he Birck Nanotechnology center offers a variety of capabilities especially in general microfabrication, electrical and physical characterization. With regards to microfabrication, the center features a variety of toolsets to enable fabrication of most devices from scratch to finish. These include lithography tools, such as aligners, metallization tools, such as evaporators and sputters, processing tools, such as etchers, and finally packaging tools, such as wire bonders, dicing saws, and pick‐and‐place systems. In addition to the fabrication capabilities, the center has a large selection of electrical and surface characterization systems, such as different types of probe stations and confocal microscopes to name a few. In each of these categories, the center features some unique tools such as maskless aligners, etc that could be of great benefit to the user.