Plasmon-phonon hybridization in doped semiconductors, phonon linewidths due to phonon-dressed-electron coupling, and excitations in 2D magnetic materials

The coupling between elementary excitations in materials such as electrons, plasmons, phonons, photons, and magnons give rise to interesting phenomena, where recently developed first-principles computational techniques play an important role. In this presentation, I will talk about first-principles methods to calculate the plasmon-phonon hybridization in doped semiconductors [1] and the non-adiabatic phonon self-energy due to coupling to electrons with finite linewidths [2]. Then, I will switch gears to the first-principles investigation of 2D magnetic materials, in which, different from the condition for Mermin-Wagner theorem, magnetic anisotropy can give rise to magnetic order. I will explain how different transition-metal phosphorus trisulfides have different types of magnetic anisotropy [3], possible candidates to observe the BKT transition [4], and first-principles modelling of the possible excitations in 2D magnetic materials [5].

References

[1] J.-M. Lihm and C.-H. Park, "Plasmon-Phonon Hybridization in Doped Semiconductors from First Principles." Phys. Rev. Lett. 133, 116402 (2024).

[2] C.-H. Park, "Non-adiabatic phonon self-energy due to electrons with finite linewidths," arXiv:2411.12221v1.

[3] T. Y. Kim and C.-H. Park, "Magnetic Anisotropy and Magnetic Ordering of Transition-Metal Phosphorus Trisulfides," Nano Lett. 21, 10114 (2021).

[4] Y.-J. Lee, T. Y. Kim, and C.-H. Park, unpublished.

[5] M. Ghim, T. Y. Kim, and C.-H. Park, unpublished.