Ondrej L. Krivanek – The importance of the candidate’s work and its impact in the Czech Republic
                                            and abroad

Starting in the late 1970s, Ondrej L. Krivanek designed a series of electron energy loss (EEL)
spectrometers and imaging filters, first as an assistant professor at Arizona State University and
a consultant to Gatan Inc., and later as director of R&D at Gatan. These became highly successful,
with over 500 installations world-wide. He also co-authored, with Channing Ahn, the EELS Atlas, now
a standard reference for electron energy loss spectroscopy, pioneered the design and use of
slow-scan CCD cameras for electron microscopy, and developed efficient microscope aberration
diagnosis and tuning algorithms. He also initiated the development and designed the first user
interface of DigitalMicrograph, which went on to become the world’s leading electron microscopy
image acquisition and processing software. The imaging filters he designed were corrected for
second order aberrations and distortions, and he next took up the correction of third order
aberrations, a key problem in electron microscopy. Following an unsuccessful application for
funding in the US, he applied, successfully, for support to the Royal Society (jointly with L.
Michael Brown FRS and Andrew Bleloch). He then took an unpaid leave of absence from Gatan to
develop an aberration corrector for a scanning transmission electron microscope (STEM) in Cambridge
UK, together with Niklas Dellby and others. In 1997, this led to the first STEM aberration
corrector that succeeded in improving the resolution of the electron microscope it was built into.
Also in 1997 and with Niklas Dellby, he started Nion Co., where they produced a new corrector
design. In 2000 this corrector became the first commercially delivered electron microscope
aberration corrector in the world (to IBM TJ Watson Research Center), and soon after delivery it
produced the first directly interpretable sub-Å resolution images obtained by any type of an
electron microscope.  Nion correctors delivered to Oak Ridge National Laboratory produced the first
directly interpretable sub-Å resolution electron microscope images of a crystal lattice and the
first EEL spectra of single atoms in a bulk solid. Nion has since progressed onto designing and
manufacturing whole scanning transmission electron microscopes that have produced many further
world-leading results, such as atomic-resolution elemental mapping and analytical imaging in which
every individual atom is resolved and identified.  In 2013, Nion introduced a new design of a
monochromator for STEM that allowed the first demonstration of vibrational/phonon spectroscopy in
the electron microscope, and can now reach 3 meV energy resolution at 20 kV. Used in tandem with
the new Nion energy loss spectrometer, the monochromator has led to many revolutionary results.
These include a 2016 demonstration of damage-free vibrational spectroscopy of different hydrogen
environments in a biological material (Guanine), 2019 demonstrations of atomic resolution imaging
using the phonon signal and of detecting and mapping an amino acid different in just one 12C atom
being substituted by 13C (isotopic shift), and a 2020 detection of the vibrational signal from a
single Si atom.