STROBE electron microscopy lecture

In 2021, I gave a pedagogical lecture on electron microscopy to STROBE: a NSF Science and Technology Center focused on developing the fields of optical, x-ray and electron microscopy. 

Contrast transfer and noise in ptychography

During my PhD studies, I explored the image contrast mechanisms of electron ptychography, and how experiments can be designed to maximize signal and minimize the effects noise.

STEM diffraction patterns from a thick crystal

A series of convergent beam electron diffraction (CBED) patterns acquired from a zeolite sample using four-dimensional scanning transmission electron microscopy (4D-STEM).

Focused-probe STEM ptychography: developments and opportunities

In 2020, I was invited to give a virtual oral presentation at Microscopy and Microanalysis: the largest microscopy conference in the US. 

Ptychography using fast binary 4D STEM data

During my PhD studies, I demonstrated the first example of electron ptychography using a detector operating in 1-bit mode (i.e. can only count '0' or '1').  By decreasing the bit depth of the detector, sparse data sets could be acquired with a tenfold increase in acquisition speeds. Surprisingly, the ptychographic reconstructions from this data provided high-fidelity phase images at atomic resolution.

'Burning sun' diffraction patterns

An example series of convergent beam electron diffraction (CBED) patterns acquired from uranium dioxide: a material typically used in cooling rods of nuclear power plants.