DAVID FLANNIGAN
ASSOCIATE PROFESSOR
Research Interests
Our research program deals broadly with the experimental elucidation of non-equilibrium electronic and structural dynamics of inorganic, organic, and biological materials with atomic-scale spatial and femtosecond temporal resolutions. To achieve this, we use ultrafast four-dimensional electron microscopy (UEM). With UEM, we bring together the high spatial resolution of transmission electron microscopy with the ultrafast temporal resolution of short-pulsed lasers. We are able to directly visualize, in real-time, a wide variety of phenomena, including how crystal lattices respond to the excitation and relaxation of charge-carriers, the collective and coherent motions of lattices at the unit cell level, the real-space dynamics of nanoscale architectures and the effects of interfacial forces, and the effects of charge-transfer reactions on structure. Our group is highly interdisciplinary and collaborative, and our interests are broad, having foundations in materials science and engineering, chemistry, and physics. Our current interests are in three related but distinct areas: (1) energy transport and conversion in defect-laden materials, (2) structural dynamics, phase transitions, and energy transport properties of strongly-correlated materials, and (3) in situ TEM of laser-induced phase transformations and magnetic switching phenomena. The unifying goal of our work is to understand how atomic structure and dynamics lead to the emergence of bulk properties in materials, and how fundamental ultrafast processes of energy coupling occur on the nanoscale.
Awards
- Sigma Xi Young Investigator Award, 2018
- McKnight Presidential Fellowship, 2018
- George W. Taylor Career Development Award, 2018
- DOE Early Career Award, 2017
- NSF CAREER Award, 2017
- Beckman Young Investigator Award, 2015
- McKnight Land-Grant Assistant Professor, 2014
- 3M Nontenured Faculty Award, 2013
Selected Publications
- Flannigan, D. J.; Curtis, W. A.; VandenBussche, E. J.; Zhang, Y. Low Repetition-Rate, High-Resolution Femtosecond Transmission Electron Microscopy. J. Chem. Phys. 2022, 157, 180903. (Invited)
- Curtis, W. A.; Willis, S. A.; Flannigan, D. J. Single-Photoelectron Collection Efficiency in 4D Ultrafast Electron Microscopy. Phys. Chem. Chem. Phys. 2022, 24, 14044-14054.
- Chen, J.; Flannigan, D. J. A Quantitative Method for In Situ Pump-Beam Metrology in 4D Ultrafast Electron Microscopy. Ultramicroscopy 2022, 234, 113485.
- Gnabasik, R. A.; Suri, P. K.; Chen, J.; Flannigan, D. J. Imaging Coherent Phonons and Precursor Dynamics in LaFeAsO with 4D Ultrafast Electron Microscopy. Phys. Rev. Mater. 2022, 6, 024802.
- Zhang, Y.; Choi, M.-K.; Haugstad, G.; Tadmor, E. B.; Flannigan, D. J. Holey Substrate-Directed Strain Patterning in Bilayer MoS2. ACS Nano 2021, 15, 20253.
- Curtis, W. A.; Flannigan, D. J. Toward Å-fs-meV Resolution in Electron Microscopy: Systematic Simulation of the Temporal Spread of Single-Electron Packets. Phys. Chem. Chem. Phys. 2021, 23, 23544. (Invited, Themed Issue: Developments in Ultrafast Spectroscopy)
- Zhang, Y.; Flannigan, D. J. Imaging Nanometer Phonon Softening at Crystal Surface Steps with 4D Ultrafast Electron Microscopy. Nano Lett. 2021, 21, 7332.
- Reisbick, S. A.; Zhang, Y.; Chen, J.; Engen, P. E.; Flannigan, D. J. Coherent Phonon Disruption and Lock-In During a Photoinduced Charge-Density-Wave Phase Transition. J. Phys. Chem. Lett. 2021, 12, 6439. (Front cover article)
- Du, D. X.; Reisbick, S. A.; Flannigan, D. J. UEMtomaton: A Source-Available Platform to Aid in Start-up of Ultrafast Electron Microscopy Labs. Ultramicroscopy 2021, 223, 113235.
- VandenBussche, E. J.; Flannigan, D. J. High-Resolution Analogue of Time-Domain Phonon Spectroscopy in the Transmission Electron Microscope. Philos. Trans. R. Soc. A 2020, 378, 20190598. (Invited, Themed Issue: Dynamic In-Situ Microscopy Relating Structure and Function)

CONTACT INFORMATION
Email: flan0076@umn.edu
Phone: 612/625-3867
Office: 401 Amundson Hall
Support David Flannigan's Research
Education
- B.S., Chemistry, University of Minnesota, 2001
- Ph.D., Chemistry, University of Illinois at Urbana-Champaign, 2006
- Postdoctoral Scholar, Chemistry, California Institute of Technology, 2007-2010
- Senior Postdoctoral Scholar, Chemistry, California Institute of Technology, 2011-2012