Scattering and Instrumentation Sciences
Scattering and Instrumentation Sciences
This program area encompasses basic research in condensed matter physics and materials physics using electron, neutron, and x-ray scattering capabilities. Research includes experiment and theory that seeks to achieve a fundamental understanding of the atomic, electronic, and magnetic structures and excitations of materials as well as the relationship of these structures and excitations to the physical properties of materials. Also supported is the study of fundamental dynamics in complex materials, correlated electron systems, nanostructures, and novel systems using advanced ultrafast spectroscopy, diffraction and microscopy. The emphasis is on using time-domain approaches to provide new understanding of complex behavior, emergent phenomena, and exotic properties in condensed matter. Another increasingly important aspect is the study of the nature of materials at the nanoscale including ordering fluctuations, and the structure and composition of inhomogeneities such as defects, interfaces, surfaces, and precipitates.
Advancing the state of the art of electron beam and scanning probe techniques and instrumentation for quantitative microscopy and microanalysis is an essential element in this portfolio. The increasing complexity of energy-relevant materials such as superconductors, semiconductors, and magnets requires continuing development and improvement of next-generation x-ray and neutron scattering instrumentation for characterizing the atomic, electronic, and magnetic structures of these materials. This includes a full range of elastic, inelastic, and imaging techniques as well as ancillary technologies such as novel detectors, sample environment, data analysis, and technology for producing polarized neutrons.
- Ultrafast Materials Science
- Soft Matter Electron Microscopy
- Real Time TEM Imaging of Materials Transformations in Liquid and Gas Environments
Program Leader: Alessandra Lanzara
Co-PI's: Robert Kaindl, Joseph Orenstein
This program applies advanced ultrafast techniques to fundamental problems in condensed matter physics. The focus is on: complex materials where correlation among charges and between charge, spin, and phonons lead to new properties, and exotic phases; and novel physics at interfaces, and in nanostructured materials. Ultrafast spectroscopy provides new insight by separating correlated phenomena in the time domain with resolution shorter than the underlying coupling processes. The program is focused on three inter-related scientific themes: (1) resolving the dynamic interactions driving the correlation and pairing of charge carriers, (2) understanding competing atomically-ordered electronic phases in complex oxides, (3) understanding & controlling complex materials away from equilibrium. Unique capabilities of this program include: ultrafast X ray spectroscopy and scattering, time-resolved XUV ARPES, time-resolved MOKE, reflectivity and wave-mixing, ultrabroadband THz and mid-IR spectroscopy. These tools enable measurements of correlated phenomena on fundamental time scales, at atomic spatial scales, with momentum resolution and element specificity information that is indispensable for achieving new insight onto the emergent physics of complex materials and nanostructures.
M.C. Langner, S. Roy, S.K. Mishra, J.C.T. Lee, X.W. Shi, M.A. Hossain, Y.-D. Chuang, S. Seki, Y. Tokura, S.D. Kevan, and R. W. Schoenlein. Coupled skyrmion sublattices in Cu2OSeO3 revealed by resonant soft X-ray scattering. Phys. Rev. Lett. 112, 167202 (2014).
S.Y. Zhou, M.C. Langner, Y. Zhu, Y.-D. Chuang, M. Rini, T.E. Glover, M.P. Hertlein, A.G. Cruz Gonzalez, N. Tahir, Y. Tomioka, Y. Tokura, Z. Hussain, and R.W. Schoenlein. Glass-like recovery of antiferromagnetic spin ordering in a photo-excited manganite Pr0.7Ca0.3MnO3. Sci. Rep. 4, 4050 (2014).
G. Coslovich, B. Huber, W.-S. Lee, Y.-D. Chuang, Y. Zhu, T. Sasagawa, Z. Hussain, H. A. Bechtel, M.C. Martin, Z.-X. Shen, R.W. Schoenlein, and R.A. Kaindl. Ultrafast charge localization in a stripe-phase nickelate. Nature Communications 4, 2643 (2013).
J.D. Koralek, D. Meier, J.P. Hinton, A. Bauer, S.A. Paramswaran, A. Vishwanath, R. Ramesh, R.W. Schoenlein, C. Pfleiderer, and J. Orenstein. Observation of coherent helimagnons and Gilbert damping in an itinerant magnet. Phys. Rev. Lett. 109, 247204 (2012).top
Program Leader: Nitash Balsara
Co-PI's: Ken Downing, David Prendergast, Jeffrey Kortright, Andrew Minor, Ronald Zuckermann
We investigate charge transport in polymer membranes by electron scattering and microscopy. Our focus is self-assembled nanostructures formed by bio-inspired peptoids and synthetic block copolymers, within which ion transport is restricted to one of the nanostructures. We aim to determine the geometry and chain configurations that lead to the most efficient solid-phase ion-transporting channel. Spatially resolved electron microscopy and energy-loss spectroscopy are crucial for obtaining the relationship between morphology and transport. Our microscopy techniques focus on maximizing spatial and energy resolution while minimizing radiation exposure and damage. In order to manipulate and detect the incident, transmitted, and scattered electrons we will use aberration-correctors, high brightness instruments, and novel 3D image reconstruction algorithms. We have designed in-situ electron microscopy experiments to investigate the dynamic nature of soft materials on molecular and sub-molecular length. This project will investigate whether or not the resolution in soft materials can be extended to sub-nanometer length scales. We will develop materials with unique properties, such as membranes that become wetter when they are heated in air and mechanically robust solid electrolytes for battery applications.
K.J. Harry, D.T. Hallinan, D.Y. Parkinson, A.A. MacDowell, and N.P. Balsara. Detection of Subsurface Structures Underneath Dendrites formed on Cycled Lithium Metal Electrodes. Nature Materials 13, 69-73 (2014).
F.I. Allen, P. Ercius, M.A. Modestino, R.A. Segalman, N.P. Balsara, and A.M. Minor. Deciphering the Three-Dimensional Morphology of Block Copolymer Thin Films by Transmission Electron Microscopy. Micron 44, 442-450 (2013).
P. Knychala, M. Dziecielski, M. Banaszak, and N.P. Balsara. Phase Behavior of Ionic Block Copolymers Studied by a Minimal Lattice Model with Short-Range Interactions. Macromolecules 46, 5724-5730 (2013).
J. Sun, A.A. Teran, X. Liao, N.P. Balsara, and R.N. Zuckermann. Nanoscale Phase Separation in Sequence-Defined Peptoid Diblock Copolymers. Journal of the American Chemical Society 135, 14119-14124 (2013).
J. Sung, G.M. Stone, N.P. Balsara, and R.N. Zuckermann, Structure-Conductivity Relationship for Peptoid-Based PEO-Mimetic Polymer Electrolytes. Macromolecules 45(12), 5151-5156 (2012).top
Program Leader: Haimei Zheng
The understanding of materials’ interaction with their environments provides guidance for designing functional materials for specific applications. Our interest comprises a wide range of physical and chemical processes of materials at atomic scale, and our efforts focus on the study of materials transformation under working environment key to the fabrication of inexpensive and efficient energy devices.
We use laser-matter interaction and non-equilibrium growth to develop novel functional materials for battery, electrocatalysis or other applications. By the development of in situ liquid and gas transmission electron microscopy (TEM), we study nucleation and growth, mass transport at interfaces and ion exchanges of materials in situ operando. This includes engineering the sample test environments such as applying an applied electric bias, elevated temperature, reduction or oxidation environmental stimulus. These efforts open the opportunities to address fundamental materials issues in energy conversion and energy storage applications.
Our research consists of the following components: 1) Mechanistic study of nanoparticle growth and transformation in liquids; 2) Structural dynamics of nanoparticle catalysis; 3) Mass transport and interfaces in electrochemical processes; 4) Non-equilibrium processing and characterization of novel functional materials.
Z. Zeng, W. Liang, H.G. Liao, H.L. Xin, Y.H. Chu, and H. Zheng. Visualization of electrode-electrolyte interfaces in LiPF6/EC/DEC electrolyte for lithium ion batteries via in-situ TEM. Nano Lett. 14, 1745 (2014).
H. L. Xin, S. Alayoglu, R. Tao, A. Genc, C. Wang, L. Kovarik, E. Stach, L -W. Wang, M. Salmeron, G. Somorjai, H. Zheng. Revealing the Atomic Restructuring of Pt-Co Nanoparticles. Nano Lett. nl500553a (2014).
H. Liao, L. Cui, S. Whitelam, and H. Zheng. Real time imaging Pt3Fe nanorod growth in solution. Science 336, 1011 (2012).top