Crystal Interface Lab. Seminar Series
In-situ Dynamic Transmission Electron Microscopy (DTEM)
byProfessor Nigel D. Browning
1Condensed Matter and Materials Division, Physical and Life Sciences Directorate,
Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, Ca 94550. USA
2
Department of Chemical Engineering and Materials Science,
University of California-Davis, One Shields Ave, Davis, Ca 95616. USA
3
Department of Molecular and Cellular Biology,
University of California-Davis, One Shields Ave, Davis, Ca 95616. USA

The need to be able to observe dynamic phenomena in materials systems with both high spatial(~1nm or better) and high temporal (~1µs or faster) resolution has led to the development of a
dynamic transmission electron microscope (DTEM). The high temporal resolution is achieved inthe DTEM by using a short pulse laser to create the pulse of electrons through photo-emission (herethe duration of the electron pulse is approximately the same as the duration of the laser pulse).
This pulse of electrons is propagated down the microscope column in the same way as in aconventional high-resolution TEM. The only difference is that the spatial resolution is limited by theelectron-electron interactions in the pulse (a typical 10ns pulse contains ~108 electrons). To
synchronize this pulse of electrons with a particular dynamic event, a second laser is used to “drive”
the sample a defined time interval prior to the arrival of the laser pulse. The important aspect of thisdynamic DTEM modification is that one pulse of electrons is used to form the whole image, allowing
irreversible transitions and cumulative phenomena such as nucleation and growth, to be studied
directly in the microscope. The use of the drive laser for fast heating of the specimen presents
differences and several advantages over conventional resistive heating in-situ TEM – such as theability to drive the sample into non-equilibrium states. So far, the drive laser has been used forin-situ processing of nanoscale materials, rapid and high temperature phase transformations,controlled thermal activation of materials. In this presentation, a summary of the development ofin-situ stages for both the existing DTEM at LLNL and a new aberration corrected DTEM at
UC-Davis will be described. Particular attention will be paid to the potential for gas stages to studycatalytic processes and liquid stages to study biological specimens in their live hydrated states. The
potential improvements in spatial and temporal resolution that can be expected through theimplementation of upgrades to the lasers, electron optics and detectors used in the new DTEM will
also be discussed along with the correlation of dynamic results with conventional high resolution
imaging and spectroscopic methods in TEM.
Aspects of this work are performed under the auspices of the U.S. Department of E nergy by Lawrence
Livermore National Laborat ory and support ed by the Office of Science, Offic e of Basic Energy Sciences,
Division of Materials Sciences and Engineering, of the U.S. Department of Energy under Contract
DE-A C52-07NA 27344. Aspects of this work at UC-Davis were supported by DOE NNSA-SSAA grant
number DE-FG52-06NA 26213 and NIH grant number RR025032-01.

May 12 (Thursday), 2011 15:00 -16:30
Main meeting room at Institute of Engineering Innovation, UT(工学部総合研究機構

Organizer: Prof. Yuichi Ikuhara
TEL: 03-5841-7688
E-mail: ikuhara@sigma.t.u-tokyo.ac.jp

9 号館 1 階大会議室)