• Anisotropic in-plane dielectric and ferroelectric properties of tensile-strained BaTiO3 films with three different crystallographic orientations 

      Ræder, Trygve Magnus; Holstad, Theodor Secanell; Nylund, Inger-Emma; Glaum, Julia; Einarsrud, Mari-Ann; Meier, Dennis; Grande, Tor (Peer reviewed; Journal article, 2021)
      Ferroelectric properties of films can be tailored by strain engineering, but a wider space for property engineering can be opened by including crystal anisotropy. Here, we demonstrate a huge anisotropy in the dielectric ...
    • Atomic-scale 3D imaging of individual dopant atoms in an oxide semiconductor 

      Hunnestad, Kasper Aas; Hatzoglou, Constantinos; Zeeshan, Muhammad; Vullum, Per Erik; Yan, Zewu; Bourret, Edith; Van Helvoort, Antonius; Selbach, Sverre Magnus; Meier, Dennis (Peer reviewed; Journal article, 2022)
      The physical properties of semiconductors are controlled by chemical doping. In oxide semiconductors, small variations in the density of dopant atoms can completely change the local electric and magnetic responses caused ...
    • Building a framework for domain characterisation of K3Nb3B2O12 by electron diffraction and transmission electron microscopy 

      Linnerud, Marthe (Master thesis, 2022)
      Det ortorombiske, ferroelastiske oksidet K3Nb3B2O12 (KNBO) har blitt foreslått som et kandidatmateriale for domeneveggbasert teknologi på grunn av dets foreslåtte (anti)ferroelektriske egenskaper. Tidligere har det blitt ...
    • Charged domain walls in improper ferroelectric hexagonal manganites and gallates 

      Småbråten, Didrik Rene; Meier, Quintin Noel; Skjærvø, Sandra Helen; Inzani, Katherine; Meier, Dennis; Selbach, Sverre Magnus (Journal article; Peer reviewed, 2018)
      Ferroelectric domain walls are attracting broad attention as atomic-scale switches, diodes and mobile wires for next-generation nanoelectronics. Charged domain walls in improper ferroelectrics are particularly interesting ...
    • Charged ferroelectric domain walls in K2MgWP2O10 and K3Nb3B2O12 studied by transmission electron microscopy 

      Topstad, Mats (Master thesis, 2023)
      Ladet domenevegg teknikk er et fremvoksende og spennende felt som fokuserer på å manipulere de funksjonelle egenskapene til domenevegger. To lovende ferroelektriske oksider, K2MgWP2O10 (KMWPO) og K3Nb3B2O12 (KNBO), er her ...
    • Conductivity control via minimally invasive anti-Frenkel defects in a functional oxide 

      Evans, Donald; Holstad, Theodor Secanell; Mosberg, Aleksander Buseth; Småbråten, Didrik Rene; Vullum, Per Erik; Dadlani, Anup; Shapovalov, Konstantin; Yan, Zewu; Bourret, Edith; Gao, David Zhe; Akola, Jaakko; Torgersen, Jan; Van Helvoort, Antonius; Selbach, Sverre Magnus; Meier, Dennis (Peer reviewed; Journal article, 2020)
      Utilizing quantum effects in complex oxides, such as magnetism, multiferroicity and superconductivity, requires atomic-level control of the material’s structure and composition. In contrast, the continuous conductivity ...
    • Confinement-Driven Inverse Domain Scaling in Polycrystalline ErMnO3 

      Schultheiss, Jan; Xue, Fei; Roede, Erik Dobloug; Ånes, Håkon Wiik; Danmo, Frida Hemstad; Selbach, Sverre Magnus; Chen, Long-Qing; Meier, Dennis (Peer reviewed; Journal article, 2022)
      The research on topological phenomena in ferroelectric materials has revolutionized the way people understand polar order. Intriguing examples are polar skyrmions, vortex/anti-vortex structures, and ferroelectric ...
    • Contact-free reversible switching of improper ferroelectric domains by electron and ion irradiation 

      Roede, Erik Dobloug; Mosberg, Aleksander Buseth; Evans, Donald; Bourret, Edith; Yan, Zewu; Van Helvoort, Antonius; Meier, Dennis (Peer reviewed; Journal article, 2021)
      Focused ion beam (FIB) and scanning electron microscopy (SEM) are used to reversibly switch improper ferroelectric domains in the hexagonal manganite ErMnO3. Surface charging is achieved by local ion (positive charging) ...
    • Correlating laser energy with compositional and atomic-level information of oxides in atom probe tomography 

      Hunnestad, Kasper Aas; Hatzoglou, hatzoglou; Vurpillot, F.; Nylund, Inger-Emma; Yan, Z.; Bourret, E.; Van Helvoort, Antonius; Meier, Dennis (Peer reviewed; Journal article, 2023)
      Atom probe tomography (APT) is a 3D analysis technique that offers unique chemical accuracy and sensitivity with sub-nanometer spatial resolution. There is an increasing interest in the application of APT to complex oxides ...
    • Defect chemistry and ferroelectric domain walls in hexagonal manganites 

      Småbråten, Didrik René (Doctoral theses at NTNU;2018:263, Doctoral thesis, 2018)
      The hexagonal manganites h-RMnO3 (R=Y, In, Sc, Ho-Lu) have been studied the last two decades for their exotic and diverse functional properties. Their large chemical flexibility makes this material class an ideal chemical ...
    • Domain wall mobility and roughening in doped ferroelectric hexagonal manganites 

      Småbråten, Didrik Rene; Holstad, Theodor Secanell; Evans, Donald; Zewu, Yan; Bourret, Edith; Meier, Dennis; Selbach, Sverre Magnus (Peer reviewed; Journal article, 2020)
      The macroscopic performance of ferroelectric and piezoelectric devices depends strongly on domain wall dynamics. It is clear that structural defects, such as vacancies, interstitials, and dopants codetermine the dynamics, ...
    • Domain-Pattern Transfer across an Artificial Magnetoelectric Interface 

      De Luca, Gabriele; Schoenherr, Peggy; Mendil, Johannes; Meier, Dennis; Fiebig, Manfred; Trassin, Morgan (Journal article; Peer reviewed, 2018)
      Magnetoelectric interfaces provide efficient pathways for manipulating the magnetic order with low-power-consuming electric fields. A prime example of this is the voltage-controlled domain-pattern transfer from a multiferroic ...
    • Domains and domain walls in ferroic materials 

      Meier, Dennis; Valanoor, Nagarajan; Zhang, Qi; Lee, Donghwa (Peer reviewed; Journal article, 2021)
      Ferroic materials exhibit long-range order with respect to their elastic, electric, or magnetic properties, giving rise to fascinating physics and functional properties that are used in, e.g., state-of-the-art sensor ...
    • Electrical half-wave rectification at ferroelectric domain walls 

      Schaab, Jakob; Skjærvø, Sandra Helen; Krohns, Stephan; Dai, Xiaoyu; Holtz, Megan, E.; Cano, Andrés; Lilienblum, Martin; Yan, Zewu; Bourret, Edith; Muller, David A.; Fiebig, Manfred; Selbach, Sverre Magnus; Meier, Dennis (Journal article; Peer reviewed, 2018)
      Domain walls in ferroelectric semiconductors show promise as multifunctional two-dimensional elements for next-generation nanotechnology. Electric fields, for example, can control the direct-current resistance and reversibly ...
    • Electromechanics of Domain Walls in Uniaxial Ferroelectrics 

      Lu, Haidong; Tan, Yueze; Richarz, Leonie; He, Jiali; Wang, Bo; Meier, Dennis; Chen, Long-Qing; Gruverman, Alexei (Peer reviewed; Journal article, 2023)
      Piezoresponse force microscopy (PFM) is used for investigation of the electromechanical behavior of the head-to-head (H-H) and tail-to-tail (T-T) domain walls on the non-polar surfaces of three uniaxial ferroelectric ...
    • Electronic bulk and domain wall properties in B-site doped hexagonal ErMnO3 

      Holstad, Theodor S.; Evans, Donald; Ruff, Alexander; Småbråten, Didrik Rene; Schaab, Jakob; Tzschaschel, Christian; Yan, Zewu; Bourret, Edith; Selbach, Sverre Magnus; Krohns, Stephan; Meier, Dennis (Journal article; Peer reviewed, 2018)
      Acceptor and donor doping is a standard for tailoring semiconductors. More recently, doping was adapted to optimize the behavior at ferroelectric domain walls. In contrast to more than a century of research on semiconductors, ...
    • Electrostatic potential mapping at ferroelectric domain walls by low-temperature photoemission electron microscopy 

      Schaab, Jakob; Shapovalov, Konstantin; Schoenherr, Peggy; Hackl, Johanna; Khan, Muhammad Imtiaz; Hentschel, Mario; Yan, Zewu; Bourret, Edith; Schneider, Claus M.; Nemsak, Slavomír; Stengel, Massimiliano; Cano, Andrés; Meier, Dennis (Journal article; Peer reviewed, 2019)
      Low-temperature X-ray photoemission electron microscopy (X-PEEM) is used to measure the electric potential at domain walls in improper ferroelectric Er0.99Ca0.01MnO3. By combining X-PEEM with scanning probe microscopy and ...
    • Emergent nanoscale functionality in uniaxial ferroelectrics 

      Holstad, Theodor Secanell (Doctoral theses at NTNU;2020:138, Doctoral thesis, 2020)
      This thesis has been focused on the characterization and manipulation of the electronic nanoscale properties of domains and domain walls in uniaxial ferroelectrics. Two classes of uniaxial ferroelectrics have been investigated, ...
    • Ferroelectric Domain Engineering Using Structural Defect Ordering 

      Gradauskaite, Elzbieta; Hunnestad, Kasper Aas; Meier, Quintin; Meier, Dennis; Trassin, Morgan (Peer reviewed; Journal article, 2022)
      Ferroelectrics have become indispensable in the development of energy-efficient oxide electronics. Their domain state is closely linked to the final device functionality, making domain engineering in technology-compatible ...
    • FIB and Functional Ferroics: Structuring and Correlated Microscopy 

      Roede, Erik Dobloug (Doctoral theses at NTNU;2022:156, Doctoral thesis, 2022)
      Norsk sammendrag FIB og funksjonelle ferroiske materialer For å fortsette utviklingen av raskere og mer energieffektiv elektronikk er vi nødt til å utnytte nye fysiske fenomener. I dette arbeidet studeres ferroiske ...