Michael A. O'Keefe (born 8 September 1942, in

East Melbourne East Melbourne is an inner-city suburb in Melbourne, Victoria, Australia, east of Melbourne's Central Business District, located within the City of Melbourne local government area. East Melbourne recorded a population of 4,896 at the 2021 ce ...

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

) is a physicist who has worked in

materials science Materials science is an interdisciplinary field of researching and discovering materials. Materials engineering is an engineering field of finding uses for materials in other fields and industries. The intellectual origins of materials sci ...

and

electron microscopy An electron microscope is a microscope that uses a beam of electrons as a source of illumination. It uses electron optics that are analogous to the glass lenses of an optical light microscope to control the electron beam, for instance focusing i ...

. He is perhaps best known for his production of the seminal computer code for modeling of

high-resolution transmission electron microscopy High-resolution transmission electron microscopy is an imaging mode of specialized transmission electron microscopes that allows for direct imaging of the atomic structure of samples. It is a powerful tool to study properties of materials on the ...

(HRTEM) images; his software was later made available as part of the DeepView package for remote electron microscopy and control. O'Keefe's tutorial on theory and application of high-resolution electron microscope image simulation is available online. O'Keefe has established methods of quantifying resolution quality, and methods of deriving accurate atom positions from high-resolution images. He used these methods to help establish high-resolution electron microscopy as a precise science; in addition to its more-pedestrian role of pictorial confirmation of nano measurements, he demonstrated HRTEM's value in measurement of nano-properties. The video and associated slides illustrate the role of his work in providing tools for nano-characterization. O'Keefe designed and developed the one-

Ångström The angstrom (; ) is a unit of length equal to m; that is, one ten-billionth of a metre, a hundred-millionth of a centimetre, 0.1 nanometre, or 100 picometres. The unit is named after the Swedish physicist Anders Jonas Ångström (1814–18 ...

microscope (OÅM) for the

National Center for Electron Microscopy The National Center for Electron Microscopy (NCEM) is a U.S. Department of Energy national user facility at Lawrence Berkeley National Laboratory in Berkeley, California, for unclassified scientific research using advanced electron microscopy ...

Lawrence Berkeley National Laboratory Lawrence Berkeley National Laboratory (LBNL, Berkeley Lab) is a Federally funded research and development centers, federally funded research and development center in the Berkeley Hills, hills of Berkeley, California, United States. Established i ...

based on an

FEI Company FEI Company (Field Electron and Ion Company) was an American company that designed, manufactured, and supported microscope technology. Headquartered in Hillsboro, Oregon, FEI had over 2,800 employees and sales and service operations in more than ...

CM300 microscope that he modified extensively to improve coherence and correct three-fold astigmatism. He was successful in breaking the "one-Ångström barrier" to resolution using his combination of hardware and software correction of microscope aberrations. He produced the first HRTEM images to show

carbon Carbon () is a chemical element; it has chemical symbol, symbol C and atomic number 6. It is nonmetallic and tetravalence, tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 ...

atoms separated by less than one Ångström in

diamond Diamond is a Allotropes of carbon, solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Diamond is tasteless, odourless, strong, brittle solid, colourless in pure form, a poor conductor of e ...

(0.89 Å) and

silicon Silicon is a chemical element; it has symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic lustre, and is a tetravalent metalloid (sometimes considered a non-metal) and semiconductor. It is a membe ...

atoms in crystalline silicon (0.78 Å)—an example of his silicon work appears on a webpage at the Department of Energy. His OÅM was the first HRTEM able to image the smallest metal atoms (

lithium Lithium (from , , ) is a chemical element; it has chemical symbol, symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard temperature and pressure, standard conditions, it is the least dense metal and the ...

) in

lithium battery Lithium battery may refer to: * Lithium metal battery, a non-rechargeable battery with lithium as an anode ** Lithium–air battery ** Lithium–iron disulfide battery ** Lithium–sulfur battery ** Nickel–lithium battery ** Rechargeable li ...

materials. Building on his work designing and operating his one-

microscope (OÅM), O'Keefe produced the design for the LBNL TEAM (transmission electron aspheric microscope) able to resolve atoms in the deep sub-Ångström resolution region (less than 0.5 Å) using a hardware electron-wave phase-corrector (Cs corrector) in combination with a coherence-enhancing electron-beam monochromator. O'Keefe was elected president of the

Microscopy Society of America The Microscopy Society of America (MSA), founded in 1942 as The Electron Microscope Society of America, is a non-profit organization that provides microanalytical facilities for studies within the sciences. Currently, there are approximately 3000 me ...

in 2007.

References

{{DEFAULTSORT:Okeefe, Michael A. Australian physicists 1942 births Living people