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Lifshitz Transition and Band Structure Evolution in Alkali Metal Intercalated 1T′-MoTe 2

Park, Joohyung [Univ. of Arizona, Tucson, AZ (United States)] (ORCID:0000000254094749)·Batyrkhanov, Ayan N. [Univ. of Arizona, Tucson, AZ (United States)]·Brandhoff, Jonas [Friedrich Schiller Univ., Jena (Germany)]·Otto, Felix [Friedrich Schiller Univ., Jena (Germany)] (ORCID:0000000223275950)·Gruenewald, Marco [Friedrich Schiller Univ., Jena (Germany)] (ORCID:0000000315457831)·Schaal, Maximilian [Friedrich Schiller Univ., Jena (Germany)] (ORCID:0000000345331666)·Hus, Saban [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)] (ORCID:0000000234109878)·Fritz, Torsten [Univ. of Arizona, Tucson, AZ (United States); Friedrich Schiller Univ., Jena (Germany)] (ORCID:0000000169041909)·Göltl, Florian [Univ. of Arizona, Tucson, AZ (United States)] (ORCID:0000000272170450)·Li, An-Ping [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)] (ORCID:0000000344007493)·Monti, Oliver L. A. [Univ. of Arizona, Tucson, AZ (United States)] (ORCID:0000000209747253)
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Abstract

In van der Waals materials, coupling between adjacent layers is weak, and consequently interlayer interactions are weakly screened. This opens the possibility to profoundly modify the electronic structure, e.g., by applying electric fields or with adsorbates. Here, in this study, we show for the case of the topologically trivial semimetal 1T′-MoTe 2 that potassium dosing at room temperature significantly transforms its band structure. With a combination of angle-resolved photoemission spectroscopy, scanning tunneling microscopy, X-ray photoemission spectroscopy, and density functional theory we show that (i) for small concentrations of K, 1T′-MoTe 2 undergoes a Lifshitz transition with the electronic structure shifting rigidly, and (ii) for larger K concentrations 1T′-MoTe 2 undergoes significant band structure transformation. Our results demonstrate that the origin of this electronic structure change stems from alkali metal intercalation.

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Park, Joohyung [Univ. of Arizona, Tucson, AZ (United States)] (ORCID:0000000254094749), Batyrkhanov, Ayan N. [Univ. of Arizona, Tucson, AZ (United States)], Brandhoff, Jonas [Friedrich Schiller Univ., Jena (Germany)], Otto, Felix [Friedrich Schiller Univ., Jena (Germany)] (ORCID:0000000223275950), Gruenewald, Marco [Friedrich Schiller Univ., Jena (Germany)] (ORCID:0000000315457831), Schaal, Maximilian [Friedrich Schiller Univ., Jena (Germany)] (ORCID:0000000345331666), Hus, Saban [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)] (ORCID:0000000234109878), Fritz, Torsten [Univ. of Arizona, Tucson, AZ (United States); Friedrich Schiller Univ., Jena (Germany)] (ORCID:0000000169041909), Göltl, Florian [Univ. of Arizona, Tucson, AZ (United States)] (ORCID:0000000272170450), Li, An-Ping [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)] (ORCID:0000000344007493), Monti, Oliver L. A. [Univ. of Arizona, Tucson, AZ (United States)] (ORCID:0000000209747253). 2025-02-26. Lifshitz Transition and Band Structure Evolution in Alkali Metal Intercalated 1T′-MoTe 2. https://doi.org/10.1021/acs.jpcc.4c07689

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