Colloquium on Solid State Theory: Vertex corrections to optical conductivity in the 2D Hubbard model
by
DrAnna Kauch(TU Wien)
→
Europe/Berlin
4064 (Campus Bahrenfeld)
4064
Campus Bahrenfeld
Notkestr. 9-11
Description
Abstract:
Susceptibilities and optical conductivity are examples of two-particle response functions that are the key quantities for connecting theoretical predictions with experimental results. It can however become highly nontrivial to calculate them, especially in cases when vertex corrections are important. In my talk I will focus on diagrammatic approaches and numerical methods that allow for computing response functions at the two-particle level [1], in particular the optical conductivity [2]. I will then present results obtained with the parquet equations method. The parquet equations allow to categorize vertex corrections depending on the dominant scattering channel they arise from, e.g. particle-hole or particle-particle -- this is so so-called parquet decomposition [2]. Another classification is possible in terms of bosonized diagrams, corresponding to single- or multi-boson exchange [3,4]. I will present results of those decompositions for optical conductivity in the 2D Hubbard model and give an outlook on how such decompositions can help in constructing simpler approximations.
[1] J. Kaufmann et al. Phys. Rev. B 103, 035120 (2021)
[2] A. Kauch et al. Phys. Rev. Lett. 124, 047401 (2020)
[3] F. Krien, A. Kauch, K. Held, Phys. Rev. Res. 3, 013149 (2021)