Print Email Facebook Twitter Edge-induced excitations in Bi2Te3 from spatially-resolved electron energy-gain spectroscopy Title Edge-induced excitations in Bi2Te3 from spatially-resolved electron energy-gain spectroscopy Author La, H.L. (TU Delft QN/Conesa-Boj Lab; Kavli institute of nanoscience Delft) Brokkelkamp, A.R. (TU Delft QN/Conesa-Boj Lab; Kavli institute of nanoscience Delft) van der Lippe, Stijn (Student TU Delft) ter Hoeve, Jaco (Vrije Universiteit Amsterdam; Nikhef) Rojo, Juan (Vrije Universiteit Amsterdam; Nikhef) Conesa Boj, S. (TU Delft QN/Conesa-Boj Lab; Kavli institute of nanoscience Delft) Date 2023 Abstract Among the many potential applications of topological insulator materials, their broad potential for the development of novel tunable plasmonics at THz and mid-infrared frequencies for quantum computing, terahertz detectors, and spintronic devices is particularly attractive. The required understanding of the intricate relationship between nanoscale crystal structure and the properties of the resulting plasmonic resonances remains, however, elusive for these materials. Specifically, edge- and surface-induced plasmonic resonances, and other collective excitations, are often buried beneath the continuum of electronic transitions, making it difficult to isolate and interpret these signals using techniques such as electron energy-loss spectroscopy (EELS). Here we focus on the experimentally clean energy-gain EELS region to characterise collective excitations in the topologically insulating material Bi2Te3 and correlate them with the underlying crystalline structure with nanoscale resolution. We identify with high significance the presence of a distinct energy-gain peak around −0.8eV, with spatially-resolved maps revealing that its intensity is markedly enhanced at the edge regions of the specimen. Our findings illustrate the reach of energy-gain EELS analyses to accurately map collective excitations in quantum materials, a key asset in the quest towards new tunable plasmonic devices. Subject BiTeCollective excitationsElectron energy-loss spectroscopyEnergy-gain peaksTopological insulators To reference this document use: http://resolver.tudelft.nl/uuid:9930ef65-ede0-4222-a208-5a2c54f60422 DOI https://doi.org/10.1016/j.ultramic.2023.113841 ISSN 0304-3991 Source Ultramicroscopy, 254 Part of collection Institutional Repository Document type journal article Rights © 2023 H.L. La, A.R. Brokkelkamp, Stijn van der Lippe, Jaco ter Hoeve, Juan Rojo, S. Conesa Boj Files PDF 1_s2.0_S0304399123001584_main.pdf 3.62 MB Close viewer /islandora/object/uuid:9930ef65-ede0-4222-a208-5a2c54f60422/datastream/OBJ/view