The Fall 2022 MatSE 590 for graduate students consists of an exciting and jam-packed schedule. MATSE 590 is a colloquium (1-3 credits) consist of a series of individual lectures by faculty, students, or outside speakers.
Graduate students will receive a weekly email with information via @psu.edu email. Graduate students are required to attend all 590 Seminars. If you have any questions, please email GradOffice@matse.psu.edu.
November 3, 2022 - "Phonons, phonons everywhere!"
Vincent Meunier, P. B. Breneman Chair and Department Head, Professor of Engineering Science and Mechanics, Penn State
Abstract
Due to spatial confinement, low-dimensional materials have attracted significant attention as emerging quantum materials. Thanks to spectacular progress in the development of atomically precise bottom-up synthesis methods, accurate knowledge of atomic content and configurations is now readily available, making it possible to create a strong link between theoretically predicted properties and their experimental observation. Several characterization techniques have been employed to improve the understanding of these materials, to establish their crystal structure, purity, and internal configurations. In particular, Raman spectroscopy has demonstrated that structural vibrations are reliable indicators of their structure and, in turn, of their fundamental properties.
In this talk, I will provide an overview of the theoretical and computational research performed in my group in the area of phonon calculations and demonstrate how quantum mechanical studies and Raman scattering are combined to determine the fundamental structural properties in an array of low-dimensional materials. In addition to discussing examples of such studies performed on twisted bilayer systems, transition metal dichalcogenides, graphene nanoribbons, and quantum dot over the past few years, I will also briefly discuss our ongoing efforts in the use of high-throughput and machine-learning methods and discuss the importance of ultra-low-frequency vibrational modes in the study of these materials. At the end of the talk, I will also present a theory of TERS (tip enhanced Raman spectroscopy).
Biography
Vincent is a computational condensed matter physicist. He is Professor of Engineering Science and Mechanics at Penn State University, where he hold the Breneman Chair and Department Head position. He earned his PhD from the University of Namur in Belgium in 1999 under the supervision of Professor Philippe Lambin. He was a Senior R&D staff member at Oak Ridge National Laboratory until 2010 when he joined Rensselaer. He has published approximately 250 papers (h-index: 72) in peer-reviewed journals and is a Fellow of the American Physical Society, the American Association for the Advancement of Science, and of the Institute of Physics. Meunier leads the Innovative Computational Material Physics (ICMP) group at Rensselaer. His research uses computation to examine the atom-level details of materials. He is particularly interested in low-dimensional materials and domains where he can collaboratively work with engineers and experimentalists to optimize these materials, starting at the atomic level and targeting functionality.