Article
Chemistry, Multidisciplinary
Hongbin Yang, Andrea Konecna, Xianghan Xu, Sang-Wook Cheong, Eric Garfunkel, F. Javier Garcia de Abajo, Philip E. Batson
Summary: This study demonstrates the existence of relatively long-lived plasmons supported by high-mobility charge carriers in La-doped BaSnO3. The properties of infrared localized surface plasmons in BLSO nanoparticles are systematically investigated using electron energy-loss spectroscopy. The results show that LSPs in BLSO exhibit a high degree of spatial confinement compared to noble metals, and have relatively low losses and high quality factors. Further analysis clarifies the relation between plasmon damping and carrier mobility in BLSO.
Article
Chemistry, Multidisciplinary
Joonsuk Park, Kiho Bae, Taeho Roy Kim, Christopher Perez, Aditya Sood, Mehdi Asheghi, Kenneth E. Goodson, Woosung Park
Summary: Transmission electron microscopy (TEM) is a crucial tool for atomic-scale material characterization, with electron irradiation causing inadvertent heating in materials. This study developed a microscopic model to quantify beam-induced heating and provide guidelines for estimating temperature rise, extending the ability to quantify thermal impact on materials down to the atomic scale.
Article
Materials Science, Multidisciplinary
N. N. Badr, F. Long, Y. Luo, M. Topping, L. K. Beland, Z. Yao, L. Balogh, M. R. Daymond
Summary: The crystal structure of the interfacial areas of a water-quenched nano-hydride was characterized using electron energy-loss spectroscopy and electron diffraction. Plasmon energy values of 17.4±0.01 eV and 18.3±0.01 eV were observed in the interfacial area, but the existence of the ζ- and γ-phases was ruled out. Simulations suggested that the observed energy values could be attributed to the delocalized nature of plasmon vibration and the effect of the interface on shifting the plasmon vibration frequency.
Article
Chemistry, Multidisciplinary
Vahagn Mkhitaryan, Katia March, Eric Nestor Tseng, Xiaoyan Li, Leonardo Scarabelli, Luis M. Liz-Marzan, Shih-Yun Chen, Luiz H. G. Tizei, Odile Stephan, Jenn-Ming Song, Mathieu Kociak, F. Javier Garcia de Abajo, Alexandre Gloter
Summary: This study demonstrates high-quality vis-IR plasmons with quality factors >60 in long copper nanowires, determined by electron energy-loss spectroscopy. By comparing measurements of silver and copper nanowires of different diameters, the relative importance of radiative and nonradiative losses in plasmons is elucidated, revealing copper's potential advantages in high-quality plasmonics in elongated nanostructures.
Article
Chemistry, Multidisciplinary
Andrea Konecna, Fadil Iyikanat, F. Javier Garcia de Abajo
Summary: The study demonstrates the possibility of identifying single isotope atom impurities in a nanostructure using transmission electron microscopy and spectroscopy. It shows the superior spatial resolution and ability to probe complete sets of vibrational modes by electron beams compared to conventional far-field spectroscopy.
Article
Chemistry, Physical
Alice Apponi, Domenica Convertino, Neeraj Mishra, Camilla Coletti, Mauro Iodice, Franco Frasconi, Federico Pilo, Narcis Silviu Blaj, Daniele Paoloni, Ilaria Rago, Giovanni De Bellis, Gianluca Cavoto, Alessandro Ruocco
Summary: In this study, accurate transmission measurements of electrons below 1 keV through suspended monolayer graphene were reported. The monolayer graphene was grown using chemical vapor deposition and transferred onto transmission electron microscopy (TEM) grids. The transparency of graphene was obtained by measuring the direct beam current and transmitted current. The experimental results showed a transmission rate ranging from about 20% to about 80% for monolayer graphene within the experimental electron energy range. The high quality and grid coverage of the suspended graphene were confirmed through various characterization techniques. Additionally, evidence of suspended monolayer graphene was observed after annealing the samples in vacuum at 550 degrees C.
Article
Nanoscience & Nanotechnology
Kenan Elibol, Clive Downing, Richard G. Hobbs
Summary: In this work, the fabrication and spectroscopic characterization of subwavelength aluminum nanocavities on suspended SiN x membranes are reported. The volume plasmon (VP) and localized surface plasmon resonance (LSPR) modes of these cavities are revealed and studied using electron energy-loss spectroscopy (EELS) and electromagnetic simulations. Dipolar LSPR modes resonant in the UV and blue regions as well as higher-energy optically dark quadrupolar and hexapolar LSPR modes are observed. The asymmetries in the fabricated nanocavities result in a mode mixing and a shift in dipolar dark LSPR modes.
Article
Chemistry, Multidisciplinary
Na Yeon Kim, Shaohong Cao, Karren L. More, Andrew R. Lupini, Jianwei Miao, Miaofang Chi
Summary: With the recent development of high-acquisition-speed pixelated detectors, 4D scanning transmission electron microscopy (4D-STEM) has become available in high-resolution electron microscopy. It provides local information on materials that is challenging to extract from bulk techniques and extends conventional STEM imaging. However, the acquisition of 4D-STEM and electron energy loss spectroscopy (EELS) simultaneously is currently not possible due to overlapping detector geometry. This study demonstrates the feasibility of modifying the detector geometry for overcoming this challenge and explores the use of a partial or defective detector for ptychographic structural imaging, enabling simultaneous multi-modal measurements with spectral information added to 4D datasets.
Article
Multidisciplinary Sciences
Sandhya Susarla, Pablo Garcia-Fernandez, Colin Ophus, Sujit Das, Pablo Aguado-Puente, Margaret McCarter, Peter Ercius, Lane W. Martin, Ramamoorthy Ramesh, Javier Junquera
Summary: This research utilizes a combination of techniques to probe the electronic structure within polar vortices in oxide superlattices at the atomic scale, finding that the peaks in Ti L-edge spectra systematically shift depending on the position of the Ti4+ cations. First-principles computations and simulations derived from first principles show good agreement with experimental results.
NATURE COMMUNICATIONS
(2021)
Article
Nanoscience & Nanotechnology
F. Granberg, X. Wang, D. Chen, K. Jin, Y. Wang, H. Bei, W. J. Weber, Y. Zhang, K. L. More, K. Nordlund, F. Djurabekova
Summary: In Ni(100-x)Fex-alloy samples, bubbles with higher He density were observed compared to elemental Ni, and they tend to be faceted. Higher Fe concentrations stabilize stacking fault structures, suppress the evolution of dislocation network, and suppress complete dislocation emission, leading to higher He density.
SCRIPTA MATERIALIA
(2021)
Article
Nanoscience & Nanotechnology
Michal Horak, Andrea Konecna, Tomas Sikola, Vlastimil Krapek
Summary: Electron energy loss spectroscopy (EELS) is commonly used to study localized surface plasmon modes of plasmonic antennas, but it has limited spectral resolution and difficulty in resolving closely spaced modes. In this study, we address this issue by analyzing the plasmon modes of a dimer plasmonic antenna composed of two gold discs. We propose metrics based on spectral and spatial sensitivity to resolve the modes and validate them through electrodynamic simulations. Experimental data demonstrate the capability of these metrics to resolve and identify the modes, except for the transverse bonding and antibonding modes. Overall, the spatio-spectral metrics enhance the information extracted from EELS for plasmonic antennas.
Article
Physics, Multidisciplinary
F. Javier Garcia de Abajo, Eduardo J. C. Dias, Valerio Di Giulio
Summary: This study reveals the nonlinear and recoil effects in the interaction between individual low-energy electrons and samples with a discrete number of states. The research highlights the potential of free electrons to control localized excitations and delineates the boundaries of such control.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Physical
S. van Vliet, A. Troglia, E. Olsson, R. Bliem
Summary: This study combines XPS, grazing-incidence X-ray diffraction, and density functional theory calculations to demonstrate that plasmon excitation energies in transition metal silicides can reflect changes in electronic structure upon formation. By observing shifts in electron energy loss satellites, even basic experimental equipment can be used to study electron structure differences in silicides, making this approach promising for enhancing the chemical sensitivity of surface spectroscopy methods.
APPLIED SURFACE SCIENCE
(2023)
Article
Physics, Multidisciplinary
S. J. Paul, S. Moran, M. Arratia, A. El Alaoui, H. Hakobyan, W. Brooks, M. J. Amaryan, W. R. Armstrong, H. Atac, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, I Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, L. Biondo, A. S. Biselli, M. Bondi, F. Bossu, S. Boiarinov, K-Th Brinkmann, W. J. Briscoe, D. Bulumulla, V. D. Burkert, R. Capobianco, D. S. Carman, A. Celentano, V Chesnokov, T. Chetry, G. Ciullo, P. L. Cole, M. Contalbrigo, G. Costantini, A. D'Angelo, N. Dashyan, R. De Vita, M. Defurne, A. Deur, S. Diehl, C. Dilks, C. Djalali, R. Dupre, H. Egiyan, L. El Fassi, P. Eugenio, S. Fegan, A. Filippi, G. Gavalian, Y. Ghandilyan, G. P. Gilfoyle, A. A. Golubenko, G. Gosta, R. W. Gothe, K. A. Griffioen, M. Guidal, M. Hattawy, T. B. Hayward, D. Heddle, A. Hobart, M. Holtrop, Y. Ilieva, D. G. Ireland, E. L. Isupov, H. S. Jo, R. Johnston, K. Joo, S. Joosten, D. Keller, A. Khanal, M. Khandaker, W. Kim, A. Kripko, V Kubarovsky, V Lagerquist, L. Lanza, M. Leali, S. Lee, P. Lenisa, X. Li, K. Livingston, I. J. D. MacGregor, D. Marchand, V Mascagna, B. McKinnon, Z. E. Meziani, S. Migliorati, R. G. Milner, T. Mineeva, M. Mirazita, V. Mokeev, P. Moran, C. Munoz Camacho, K. Neupane, D. Nguyen, S. Niccolai, G. Niculescu, M. Osipenko, A. Ostrovidov, P. Pandey, M. Paolone, L. L. Pappalardo, R. Paremuzyan, E. Pasyuk, W. Phelps, N. Pilleux, D. Pocanic, O. Pogorelko, M. Pokhrel, J. Poudel, J. W. Price, Y. Prok, B. A. Raue, T. Reed, M. Ripani, G. Rosner, F. Sabatie, C. Salgado, A. Schmidt, R. A. Schumacher, Y. G. Sharabian, E. Shirokov, U. Shrestha, P. Simmerling, D. Sokhan, N. Sparveris, S. Stepanyan, I. I. Strakovsky, S. Strauch, J. A. Tan, R. Tyson, M. Ungaro, S. Vallarino, L. Venturelli, H. Voskanyan, E. Voutier, X. Wei, R. Wishart, M. H. Wood, N. Zachariou, Z. W. Zhao, V Ziegler, M. Zurek
Summary: We present the first measurement of dihadron angular correlations in electron-nucleus scattering. The results show a strong suppression effect for azimuthally opposite pairs, no suppression effect for nearby pairs, and an enhancement effect for pairs with large invariant mass. These findings indicate that angular correlation studies are important for understanding the formation and interaction of hadrons inside nuclei.
PHYSICAL REVIEW LETTERS
(2022)
Article
Materials Science, Coatings & Films
Yue-Zhen Huang, Shih-Chun Tseng, Yi-Hung Chen, Hung-Yin Tsai
Summary: This study investigates the role of laser ablation in the synthesis of carbon nano-flake balls in microwave plasma chemical vapor deposition. Through systematic studies, it is found that defects on the silicon substrate and the silicon carbide layer after laser ablation are key factors for the growth of CNFBs.
SURFACE & COATINGS TECHNOLOGY
(2021)
Article
Physics, Atomic, Molecular & Chemical
A. Alfonsov, B. Buechner, V. Kataev
Summary: The study proposes the use of a cantilever-based setup to overcome challenges posed by small sample sizes, enabling detection of static magnetic response and ESR signal in novel magnetic materials samples.
APPLIED MAGNETIC RESONANCE
(2022)
Article
Chemistry, Physical
Morgan C. Allison, Sabine Wurmehl, Bernd Buechner, Joseph L. Vella, Tilo Soehnel, Sascha A. Braeuninger, Hans-Henning Klauss, Maxim Avdeev, Frederick P. Marlton, Siegbert Schmid, Chris D. Ling
Summary: FeMn3Ge2Sn7O16 is a fully ordered stoichiometric phase with an undistorted hexagonal kagome' lattice of Mn2+ cations. By replacing silicon with germanium and anisotropic high-spin Fe2+ with isotropic high-spin Mn2+, the perfection of the kagome lattice is improved, ruling out single-ion anisotropy as the driving force for the unique properties of the compounds.
CHEMISTRY OF MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Vitaliy Romaka, Ahmad Omar, Wolfgang Loeser, Bernd Buechner, Sabine Wurmehl
Summary: Investigations into the thermodynamic phase diagram of Co-based Heusler phases, focusing on the quaternary region of CoCrCoAl-CoFe, revealed critical points and immiscibility regions through DFT and thermodynamic calculations, offering valuable insights for materials design.
COMPUTATIONAL MATERIALS SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Olga Kataeva, Kamil Ivshin, Kirill Metlushka, Kristina Nikitina, Vera Khrizanforova, Yulia Budnikova, Robert R. Fayzullin, Shamil Latypov, Sandra Schiemenz, Michael Bretschneider, Alexey Popov, Stanislav Avdoshenko, Yulia Krupskaya, Bernd Buchner, Martin Knupfer
Summary: A series of new charge-transfer cocrystals of F(2)TCNQ with anthracene, tetracene, and chrysene were prepared and characterized. The study revealed that face-to-face pi-pi interactions are crucial for the formation of cocrystals, but lateral noncovalent interactions also play a significant role in the supramolecular arrangement and charge transfer. UV/vis spectroscopy and electronic structure quantum chemical calculations classified these cocrystals as small-gap semiconductors with energy gaps of 0.7-1.3 eV.
CRYSTAL GROWTH & DESIGN
(2022)
Article
Nanoscience & Nanotechnology
Daniel Wolf, Sebastian Schneider, Ulrich K. Rossler, Andras Kovacs, Marcus Schmidt, Rafal E. Dunin-Borkowski, Bernd Buechner, Bernd Rellinghaus, Axel Lubk
Summary: Holographic vector-field electron tomography quantitatively reconstructed the three-dimensional magnetic texture of Bloch skyrmion tubes in FeGe with sub-10-nanometre resolution, revealing complex three-dimensional modulations and fundamental principles of skyrmion formation.
NATURE NANOTECHNOLOGY
(2022)
Article
Physics, Multidisciplinary
Rui Lou, Alexander Fedorov, Qiangwei Yin, Andrii Kuibarov, Zhijun Tu, Chunsheng Gong, Eike F. Schwier, Bernd Buechner, Hechang Lei, Sergey Borisenko
Summary: The entanglement of charge density wave (CDW), superconductivity, and topologically nontrivial electronic structure has been discovered in the kagome metal AV3Sb5 (A = K, Rb, Cs) family recently. Using high-resolution angle-resolved photoemission spectroscopy, the electronic properties of CDW and superconductivity in CsV3Sb5 are studied. The spectra around K over line exhibit a peak-dip-hump structure associated with two separate branches of dispersion, indicating the isotropic CDW gap opening below EF. The presence of a superconducting gap on both the electron band around Gamma over line and the flat band around K suggests multiband superconductivity. Our results shed light on the controversial origin of the CDW and provide insights into the relationship between CDW and superconductivity.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Physical
Lorenzo Francesco Madeo, Patrizia Sarogni, Giuseppe Cirillo, Orazio Vittorio, Valerio Voliani, Manuela Curcio, Tyler Shai-Hee, Bernd Buechner, Michael Mertig, Silke Hampel
Summary: A hybrid hydrogel was developed by loading curcumin onto graphene oxide nanosheets and blending them into an alginate hydrogel. The resulting system showed improved stability and exhibited strong anticancer effects.
Article
Multidisciplinary Sciences
Kiana Baumgaertner, Marvin Reuner, Christian Metzger, Dmytro Kutnyakhov, Michael Heber, Federico Pressacco, Chul-Hee Min, Thiago R. F. Peixoto, Mario Reiser, Chan Kim, Wei Lu, Roman Shayduk, Manuel Izquierdo, Guenter Brenner, Friedrich Roth, Achim Schoell, Serguei Molodtsov, Wilfried Wurth, Friedrich Reinert, Anders Madsen, Daria Popova-Gorelova, Markus Scholz
Summary: In this study, the authors used time-resolved momentum microscopy and orbital tomography to observe the changes in the excited-state photoelectron momentum of a bilayer pentacene film on Ag(110) using a free-electron laser. They found that the bottom layer exhibited charge redistribution induced by excitation, while the top layer showed excited-state molecular dynamics.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Maxim K. Rabchinskii, Sergey A. Ryzhkov, Nadezhda A. Besedina, Maria Brzhezinskaya, Maxim N. Malkov, Dina Yu Stolyarova, Albert F. Arutyunyan, Nikolai S. Struchkov, Svyatoslav D. Saveliev, Igor D. Diankin, Demid A. Kirilenko, Sergei Pavlov, Dmitrii Potorochin, Friedrich Roth, Maksim Gudkov, Alexander A. Gulin, Peiqing Cai, Zugang Liu, Andrey Golovin, Pavel N. Brunkov
Summary: This study focuses on the synthesis and conjugation of carboxylated reduced graphene oxide (C-xy rGO) with aptamers, followed by theoretical analysis of their conformation in the immobilized state. The research demonstrates the potential application of graphene derivatives in biosensing.
Article
Chemistry, Multidisciplinary
Lukas Graf, Fupin Liu, Marco Naumann, Friedrich Roth, Bipasha Debnath, Bernd Buechner, Yulia Krupskaya, Alexey A. Popov, Martin Knupfer
Summary: High-quality single crystals of the organic semiconductor (1,2;8,9)-dibenzopentacene were grown and characterized. The crystal structure, previously unknown, was determined using single-crystal X-ray diffraction. Optical absorption measurements showed anisotropic behavior in the ac plane of the crystals, while electron energy-loss spectroscopy revealed exciton dispersion of the Davydov components. Analysis suggested smaller electron and hole-transfer integrals in dibenzopentacene compared to pentacene. The excitation spectra exhibited momentum-dependent admixture of different types of excitons and vibrational modes.
Article
Instruments & Instrumentation
Michael Heber, Nils Wind, Dmytro Kutnyakhov, Federico Pressacco, Tiberiu Arion, Friedrich Roth, Wolfgang Eberhardt, Kai Rossnagel
Summary: A 790-nm-driven high-harmonic generation source combined with a toroidal-grating monochromator and a high-detection-efficiency photoelectron time-of-flight momentum microscope enables time- and momentum-resolved photoemission spectroscopy. Three-dimensional Fermi surface mapping is demonstrated on a graphene-covered surface, providing a basis for studying ultrafast dynamics.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2022)
Article
Materials Science, Multidisciplinary
Martin Knupfer, Fabian Jerzembeck, Naoki Kikugawa, Friedrich Roth, Joerg Fink
Summary: Studies on charge carrier plasmon excitations in Sr2RuO4 using transmission electron energy-loss spectroscopy reveal the dispersion and width of the plasmon as a function of momentum transfer. The dispersion can be explained qualitatively with unrenormalized tight-binding band structure based on random phase approximation calculations. The constant long-wavelength width of the plasmon suggests its origin in interband transitions rather than quantum critical fluctuations.
Article
Materials Science, Multidisciplinary
D. Potorochin, R. Kurleto, O. J. Clark, E. D. L. Rienks, J. Sanchez-Barriga, F. Roth, V. Voroshnin, A. Fedorov, W. Eberhardt, B. Buechner, J. Fink
Summary: This study presents a high-resolution angle-resolved photoemission (ARPES) investigation of the nearly free-electron metal sodium, revealing a slightly smaller mass enhancement compared to previous studies. The observed lifetime broadening highlights the need for theories beyond the random phase approximation. Contrary to the proposed strong enhancement of scattering rates due to coupling to spin fluctuations, our results do not support this hypothesis. Additionally, comparison with earlier electron energy-loss data suggests a significant reduction in the mass enhancement of dipolar electron-hole excitations compared to monopole hole excitations, as measured by ARPES.
Article
Materials Science, Multidisciplinary
Vilmos Kocsis, David A. S. Kaib, Kira Riedl, Sebastian Gass, Paula Lampen-Kelley, David G. Mandrus, Stephen E. Nagler, Nicolas Perez, Kornelius Nielsch, Bernd Buechner, Anja U. B. Wolter, Roser Valenti
Summary: In this combined theoretical and experimental research, the anisotropic magnetic and magnetoelastic properties of the Kitaev material alpha-RuCl3 were investigated. Unusually large magnetostriction anisotropy and non-symmetric magnetic anisotropy were observed, and their origins were explained based on the relative orientation of the magnetization with respect to the crystal structure.
Article
Materials Science, Multidisciplinary
F. Bougamha, S. Selter, Y. Shemerliuk, S. Aswartham, A. Benali, B. Buechner, H-J Grafe, A. P. Dioguardi
Summary: We report the anomalous breakdown in the scaling of the microscopic magnetic susceptibility with the bulk magnetic susceptibility in Mn2P2S6. NMR spectra provide evidence for domain rotation and spin-flop transition in the magnetic state. A spin-flop-induced splitting of the NMR spectra is observed in Ni2P2S6.
