Colloquium: Nonequilibrium & nonlinear terahertz spectroscopy study on superconductors

ABSTRACT

Ultra-short laser pulses play a crucial role in advancing ultrafast time-resolved spectroscopic techniques, which are essential for detecting and characterizing non-equilibrium and nonlinear responses in quantum materials. Intense laser pulses can also trigger non-adiabatic phase transitions. In this presentation, I shall first provide a brief introduction about the equilibrium and non-equilibrium optical/THz spectroscopy, followed by a focus on our recent research on detecting Higgs modes in conventional superconductors and high-Tc cuprates using terahertz pump-terahertz probe and terahertz third harmonic generation spectroscopies.

BIOGRAPHY

Nan-Lin Wang is a chair professor at the international center for quantum materials (ICQM), School of Physics, Peking University. He also serves as a vice-president of Beijing Academy of Quantum Information Sciences. He obtained his PhD in condensed matter physics from the University of Science and Technology of China in 1992. His research focuses primarily on infrared and terahertz spectroscopy study of strongly correlated electronic systems, including high temperature superconductors, charge/spin density wave compounds, transition metal oxides/chalcogenides, heavy fermions, quantum magnetic systems, 3D Dirac/Weyl semimetals in both equilibrium and nonequilibrium states. He is a fellow of the American Physical Society.