Speaker
Description
Transition metal compounds in which electrons from partially filled d-shells strongly interact with each other keep challenging the standard theory of solids as new, emergent exotic electronic orders are experimentally observed. Despite vastly different macroscopic properties, e.g. high temperature superconductivity (HTS), electronic nematicity or density waves to cite a few, the electronic phases encountered in these quantum materials can be almost degenerate and compete with each other within complex phase diagrams. In this talk I will present a selection of novel results in 3d and 5d transition metal compounds.
I will first discuss the interesting case of the unconventional incommensurate charge-density-waves (I-CDW) in BaNi2(As1-xPx)2 [1], a (non-magnetic) nickel homologue to the Fe-based systems, which exhibits original nematic fluctuations lending support to a type of electronic nematicity, dynamical in nature. Fluctuations between degenerate nematic configurations cause a splitting of phonon lines, without lifting degeneracies nor breaking symmetries, akin to spin liquids in magnetic systems [2].
The second part will be dedicated to a very different system, SrIrO3, a paramagnetic semimetal. I will show how it is possible to magnetic polarize the conduction electrons [3] of this system and control electrically this magnetization [4], through gating-induced changes of the anomalous Berry curvature of this compound. The large tunability of this system, opens new avenues towards efficient electric-field manipulation of magnetism.
References
[1] Souliou et al. Phys. Rev. Lett. 129, 247602 (2022).
[2] Yao et al, Nature Communications 13, 4535 (2022)
[3] A. K. Jaiswal, et al. Advanced Materials 34, 2109163 (2022).
[4] A. K. Jaiswal, et al. submitted (2023).
