Upcoming events (More information to come)
Optoelectronics of Hybrid Metal Halide Pervskites for Photovoltaics
Monday, Jan. 15, 2018
118 Nieuwland Science Hall
Hybrid metal halide perovskites have shown extraordinary success as active layers in solar cells, with power conversion efficiencies rivalling existing silicon technologies. A benefit of perovskites is that they are comprised of low-cost, earth abundant materials, and perovskite thin films are easily synthesized with simple starting materials. Additionally, they exhibit exceptional optoelectronic properties, which include strong absorption across the entire visible spectrum, long charge carrier lifetimes, and high charge-carrier mobilities. Optical-pump/THz-probe (OPTP) spectroscopy has proven to be an essential technique for studying the charge-carrier dynamics and charge-carrier mobility in many of these materials including lead-based, tin-based, two-dimensional, and mixed-halide/mixed-cation perovskites. These studies have determined that the charge-carrier mobility and charge-carrier recombination dynamics are strongly dependent on chemical composition, defect density band structure, and crystallinity.
January 25 - Chunhui Du, Harvard University (More information to come)
Stability in the Homology of Configuration Spaces
Wednesday, Nov. 15, 2017
127 Hayes-Healy Hall
4 p.m., following the departmental tea at 3:30 p.m. in Hurley Hall lounge, room 257
Jennifer Wilson, of Stanford University, will illustrate some patterns in the homology of the space F_k(M) of ordered k-tuples of distinct points in a manifold M. For a fixed manifold M, as k increases, we might expect the topology of the configuration spaces F_k(M) to become increasingly complicated. Church and others showed, however, that when M is connected and open, there is a representation-theoretic sense in which the homology groups of these configuration spaces stabilize. In this talk I will explain these stability patterns, and describe higher-order stability phenomena -- relationships between unstable homology classes in different degrees -- established in recent work joint with Jeremy Miller. This project was inspired by work-in-progress of Galatius-Kupers-Randal-Williams.
A Conversation with Lisa Randall
Monday, Sept. 25, 2017
A renowned scientist and author, Professor Lisa Randall studies theoretical particle physics and cosmology at Harvard University. Her research connects theoretical insights to puzzles in our current understanding of the properties and interactions of matter, as well as explores ways to experimentally test these ideas at the Large Hadron Collider and elswhere.
She will be joined on stage by Notre Dame physicist Ani Aprahamian. A book signing will follow.