BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Talks.cam//talks.cam.ac.uk// X-WR-CALNAME:Talks.cam BEGIN:VEVENT SUMMARY:Exploring matter at the atomic scale by electron microscopy and sp ectroscopy - Ondrej L. Krivanek\, Nion R&\;D\, Kirkland\, WA and Arizon a State University\, Tempe\, AZ\, USA DTSTART:20231108T160000Z DTEND:20231108T170000Z UID:TALK207709@talks.cam.ac.uk CONTACT:Julie Smith DESCRIPTION:The latest scanning transmission electronmicroscopes (STEMs) are able to resolve and analyze individual atoms\, matter’s basi c constituents. Unlike scanning tunneling microscopes\, they are able to look inside materials. They can alsodetermine the atomic composition and other properties by spectroscopic means. The last two decades brought two developments that made electron microscopesespecially powerful: worki ng aberration correctors allowed the spatial resolution to be impr oved by about 3x\, and newly developed monochromators and spectrometers a llowed the resolution of electron energy loss spectroscopy (EELS) carried out in an EM to improve to around 3 meV. The developments have made it po ssible to image individual atoms in a wide variety of inorganic materials with ease\, and their chemical and vibrational properties to be dete rmined. Examples include monolayer materials such as graphene and BN\, in which every atom can be resolved and single atom impuri ties identified\, and determining the vibrational properties of a sin gle impurity atom.Related developments have allowed biological materi als to be analyzed in a damage-free way by aloof spectroscopy\, phonons ar ising at defects to be detected\, and phonon dispersions to be ma pped in nm-sized volumes. Nion has played a pivotal role in all these advances. My talk will review how they came about\, and illustr ate them with practical examples. It will also pay tribute to EM research carried out in Cambridge in the 1960s to 1990s\, which foresaw several of the key developments. LOCATION:Goldsmiths 2 END:VEVENT END:VCALENDAR