Penghao Zhu 

The Ohio State University

Bio: Penghao Zhu earned his PhD degree from UIUC. His research primarily focused on various aspects of topological crystalline phases, such as entanglement, magnetism, geometric response, and the bulk-boundary correspondence, in both Hermitian and non-Hermitian systems.

Abstract: Light can be rectified to a direct current by inducing real-space shifts of quasiparticles. While the shift due to photon absorption (shiftexc) has been extensively studied through the lens of quantum geometry and topology, shifts arising from intraband relaxation and interband recombination have been largely overlooked in recent decades. In this talk, I will first present our newly developed quantum geometric theory for the steady shift current in semiconductors and demonstrate that these previously overlooked shifts can surpass shiftexc by orders of magnitude. Then, I will apply the general theory to a case study of the 3D semiconductor BiTeI.