University of Nebraska-Lincoln
529A Hamilton Hall
Lincoln, NE 68588-0304
Postdoctoral fellow, Northwestern University
Postdoctoral fellow, Columbia University
Ph.D., Columbia University
B.Sc., Tsinghua University
Our group’s research interest focuses on understanding how exceptional optoelectronic properties arise from unique structural dynamics in emerging materials. A current topic of interest is on the strongly anharmonic lattice fluctuations and their implications in soft semiconductors exemplified by metal-halide perovskites. These large amplitude anharmonic collective nuclear motions are inherently tied to various intriguing material behaviors including charge carrier localization and stabilization that endows defect tolerance, local symmetry breaking that underpins multiferroicity and spin dynamics, as well as self-healing mechanisms and defect photochemistry.
New insights are uncovered by employing and developing novel forms of optical spectroscopies and microscopies. These include far-field optical techniques to measure and manipulate structural and charge dynamics in materials, near-field nano-optical methods to reveal local events and properties, as well as combining optical spectroscopies with chemical space mapping.
More generally, our research program aims to understand and engineer novel hierarchical materials featuring modular building blocks assembled by tunable secondary interactions. We investigate collective nuclear motions and study how these underlying structural dynamics impact the optoelectronic and chemical behaviors of materials ranging from supramolecular assemblies to van der Waals crystals.
Yinsheng Guo, Omer Yaffe, Trevor D. Hull, Jonathan S. Owen, David R. Reichman, Louis E. Brus. Dynamic Emission Stokes Shift and Liquid-like Dielectric Solvation of Band Edge Carriers in Lead-Halide Perovskites. Nat. Commun. 2019, 10 (1), 1175.
Yinsheng Guo, Omer Yaffe, Daniel W. Paley, Alexander N. Beecher, Trevor D. Hull, Guilherme Szpak, Jonathan S. Owen, Louis E. Brus, and Marcos A. Pimenta. “Interplay between Organic Cations and Inorganic Framework and Incommensurability in Hybrid Lead-Halide Perovskite CH3NH3PbBr3” Phys. Rev. Materials 2017, 1 (4), 42401.
Selected as Rapid Communications and Editors' Suggestion.
Omer Yaffe*, Yinsheng Guo*, Liang Z. Tan, David A. Egger, Trevor Hull, Costantinos C. Stoumpos, Fan Zheng, Tony F. Heinz, Leeor Kronik, Mercouri G. Kanatzidis, Jonathan S. Owen, Andrew M. Rappe, Marcos A. Pimenta, and Louis E. Brus. “Local Polar Fluctuations in Lead Halide Perovskite Crystals” Phys. Rev. Lett. 2017, 118 (13), 136001. * equal contribution first authorship.
Recognized as `Highly Cited Paper' (top 1%) and `Hot Paper' (top 0.1%) by Web of Science, 2017.
Yinsheng Guo, Raymond B. Smith, Zhonghua Yu, Dmitri K. Efetov, Junpu Wang, Philip Kim, Martin Z. Bazant, and Louis E. Brus. “Li Intercalation into Graphite: Direct Optical Imaging and Cahn-Hilliard Reaction Dynamics” J. Phys. Chem. Lett. 2016, 7 (11), 2151-2156.
Yinsheng Guo, Dezheng Sun, Bin Ouyang, Archana Raja, Jun Song, Tony F. Heinz, and Louis E. Brus. “Probing the Dynamics of the Metallic-to-Semiconducting Structural Phase Transformation in MoS2 Crystals” Nano Lett. 2015, 15 (8), 5081-5088.