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Updated: Mar 8, 2026
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Extremely High Excitonic g Factors in 2D Crystals by Alloy-Induced Admixing of Band States
Katarzyna Olkowska-Pucko1, Tomasz Woźniak1,2, Elena Blundo3
1University of Warsaw, Faculty of Physics, 02-093 Warsaw, Poland.
Abstract:
Monolayers (MLs) of semiconducting transition metal dichalcogenides emit light very efficiently and display rich spin-valley physics, with gyromagnetic (g) factors of about -4. Here, we investigate how these properties can be tailored by alloying. Magneto-optical spectroscopy is used to reveal the peculiar properties of excitonic complexes in Mo_{x}W_{1-x}Se_{2} MLs with different metal concentrations. We show that the alloys feature extremely high g factors for neutral excitons, that change gradually with the composition up to reaching values of the order of -10 for x≈0.2. First-principles calculations quantitatively identify the alloy-induced mixing between different conduction band valleys as the underlying mechanism originating the anomalous composition dependence of the neutral exciton g factor. The theoretical framework also suggests a high strain sensitivity of the alloys, making them promising candidates for tailor-made optoelectronic devices.
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