SKM 2021 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 23: Poster Session: Emerging Phenomena in Superconducting Low Dimensional Hybrid Systems
TT 23.2: Poster
Donnerstag, 30. September 2021, 13:30–16:00, P
Dynamics of collective modes in an unconventional charge density wave system BaNi2As2 — •Amrit raj Pokharel1, Vladimir Grigorev1, Arjan Mejas2, Amir a. Haghighirad3, Rolf Heid3, Yi Yao3, Michael Merz3, Matthieu Le tacon3, and Jure Demsar1 — 1Institute of Physics, JGU Mainz, Mainz, Germany — 2Institute of Solid State Physics, TU Wein, Vienna, Austria — 3Institute of Quantum Materials and Technologies, KIT, Karlsruhe, Germany
BaNi2As2 is a non-magnetic analogue of BaFe2As2, the parent compound of a prototype pnictide high temperature superconductor displaying superconductivity already at ambient pressure. Recent diffraction studies demonstrated the existence of two types of periodic lattice distortions above and below the triclinic phase transition, suggesting the existence of an unconventional charge-density-wave (CDW) order. Upon doping, CDW order is suppressed, resulting in a sixfold increase of the superconducting transition temperature and enhanced nematic fluctuations. Here, we apply time-resolved optical spectroscopy to investigate collective response of the CDWs in BaNi2As2. By performing temperature and excitation density dependent studies we demonstrate the existence of collective modes of the CDW order. The smooth evolution of these modes through the structural phase transition implies the CDW order in the triclinic phase evolves from the unidirectional CDW in the tetragonal phase and may indeed trigger the structural phase transition.
[1] V. Grigorev, et. al., arXiv:2102.09926 (2021)