Speaker
Description
The interaction of complex solids with intense light pulses can induce novel emergent phenomena far from equilibrium. Prominent examples include optical enhancement of the critical temperature in certain superconductors and photo-stabilization of metastable states. A common theme in materials featuring exotic out-of-equilibrium behavior is the formation of charge density waves (CDWs), i.e., a coupled modulation of the charge density and crystal lattice.
Here, we use multidimensional photoemission spectroscopy to investigate the electron dynamics in a number of CDW systems. In the prototypical CDW compound TbTe3 we track the system’s order parameter during a photoinduced CDW-to-metal transition and find a surprising stability of CDW order at elevated electronic temperatures far greater than the thermal critical temperature [1]. We demonstrate how the transient modification of the electronic band structure during the ultrafast CDW-to-metal transition impacts the elementary interactions, revealing the critical role of the phase space of electron-electron scattering [2]. Furthermore, in the van-der-Waals CDW compound TaS2, we investigate the dynamics of a photoinduced transition into a hidden state, and demonstrate its coherent control through the CDW amplitude mode.
References
[1] J. Maklar et al., Nature Commun. 12, 2499 (2021).
[2] J. Maklar et al., Phys. Rev. Lett. 128, 026406 (2022).
Abstract Number (department-wise) | PC 03 |
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Department | PC (Wolf) |