2D Terahertz spectroscopy of collective excitations

Two-dimensional terahertz spectroscopy (2DTS), a terahertz analogue of nuclear magnetic resonance, stands as a novel technique poised to address numerous open questions in complex condensed matter systems. The conventional theoretical framework, widely used for interpreting multidimensional spectra of discrete quantum-level systems, falls short in capturing the continua of collective excitations in strongly correlated materials. In this talk, we provide a pedagogical introduction to the technique in a language suitable for condensed matter systems, emphasizing its unique capabilities for interrogating the properties of these systems. We focus specifically on a prototypical example, the Josephson plasmon in layered cuprates, and discuss how this multidimensional spectroscopy technique can shed light on the underlying physics, in particular regarding temperature effects, disorder, and its phase transition.

References: https://arxiv.org/abs/2308.14849 and https://arxiv.org/abs/2401.05503.

If you would like to meet with Alex during his visit, please contact Marios Michael.