Topology and strong electron correlations are crucial ingredients in emerging quantum materials, yet their intersection in experimental systems has been relatively limited to date. Strongly correlated Weyl semimetals, particularly when magnetism is incorporated, offer a unique and fertile platform to explore emergent phenomena in novel topological matter and topological spintronics. The antiferromagnetic Weyl semimetal Mn 3 Sn exhibits many exotic physical properties such as a large spontaneous Hall effect and has recently attracted intense interest. In this work, we report synthesis of epitaxial Mn 3+ x Sn 1− x films with greatly extended compositional range in comparison with that of bulk samples. As Sn atoms are replaced by magnetic Mn atoms, the Kondo effect, which is a celebrated example of strong correlations, emerges, develops coherence, and induces a hybridization energy gap. The magnetic doping and gap opening lead to rich extraordinary properties, as exemplified by the prominent DC Hall effects and resonance-enhanced terahertz Faraday rotation.
This content will become publicly available on December 1, 2023
Charge-transfer-enhanced d – d emission in antiferromagnetic NiPS 3
The d electron plays a significant role in determining and controlling the properties of magnetic materials. However, the d electron transitions, especially d– d emission, have rarely been observed in magnetic materials due to the forbidden selection rules. Here, we report an observation of d– d emission in antiferromagnetic nickel phosphorus trisulfides (NiPS 3 ) and its strong enhancement by stacking it with monolayer tungsten disulfide (WS 2 ). We attribute the observation of the strong d– d emission enhancement to the charge transfer between NiPS 3 and WS 2 in the type-I heterostructure. The d– d emission peak splits into two peaks, D 1 and D 2 , at low temperature below 150 K, from where an energy splitting due to the trigonal crystal field is measured as 105 meV. Moreover, we find that the d– d emissions in NiPS 3 are nonpolarized lights, showing no dependence on the zigzag antiferromagnetic configuration. These results reveal rich fundamental information on the electronic and optical properties of emerging van der Waals antiferromagnetic NiPS 3 .
- Award ID(s):
- 1945364
- Publication Date:
- NSF-PAR ID:
- 10389761
- Journal Name:
- Applied Physics Reviews
- Volume:
- 9
- Issue:
- 4
- Page Range or eLocation-ID:
- 041406
- ISSN:
- 1931-9401
- Sponsoring Org:
- National Science Foundation
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