Kasper Aas Hunnestad

About

Kasper Aas Hunnestad works as a PhD candidate in the FACET group since August of 2019, in the sub group Functional Topological Systems.

Main supervisor: Professor Dennis Gerhard Meier

Co-supervisor: Professor Antonius T. J. van Helvoort

Background

Before the PhD position, Kasper completed his master thesis at the TEM Gemini Centre here at NTNU, under the supervision of Professor Antonius T. J. van Helvoort, focusing on visualizing the domain structures of ferroelectric complex oxides by transmission electron microscopy. The thesis was completed in June of 2019.

Research

His research focuses on studying the defect chemistry of complex oxides by applying an advanced technique called atom probe tomography (APT). Primarily, bulk ferroelectric systems have been the main interest looking into low concentration doping and local chemical fluctuations in connection to the microsctructure. In addition, thin films and layered structures are being investigated where the aim is to resolve 3D structures and interfaces through their chemical signature. By applying APT we are able to resolve point defects at the atomic scale and bring new experimental insight into the defect chemistry of materials heavily investigated for their potential to be used in oxide electronics.

Publications

Atomic-scale 3D imaging of individual dopant atoms in an oxide semiconductor

Research article in Nature Communication.

2023

Nordahl, Gregory; Jones, Lewys; Christiansen, Emil; Hunnestad, Kasper Aas; Nord, Magnus. (2023) Correcting for probe wandering by precession path segmentation. Ultramicroscopy
Short communication
Hunnestad, Kasper Aas; Das, Hena; Hatzoglou, hatzoglou; Holtz, Megan E.; Brooks, Charles M.; Van Helvoort, Antonius. (2023) 3D oxygen vacancy order and defect-property relations in multiferroic (LuFeO3)9/(LuFe2O4)1 superlattices. arXiv.org
Academic article
Hunnestad, Kasper Aas; Hatzoglou, hatzoglou; Vurpillot, F.; Nylund, Inger-Emma; Yan, Z.; Bourret, E.. (2023) Correlating laser energy with compositional and atomic-level information of oxides in atom probe tomography. Materials Characterization
Academic article
Hunnestad, Kasper Aas; Schultheiß, Jan; Mathiesen, Anders; Ushakov, Ivan; hatzoglou, constantinos; Van Helvoort, Antonius. (2023) Quantitative Mapping of Chemical Defects at Charged Grain Boundaries in a Ferroelectric Oxide. Advanced Materials
Academic article
hatzoglou, constantinos; Da Costa, Grald; Wells, Peter; Ren, Xiaochen; Geiser, Brian P; Larson, David J. (2023) Introducing a Dynamic Reconstruction Methodology for Multilayered Structures in Atom Probe Tomography. Microscopy and Microanalysis
Academic article

2022

Hunnestad, Kasper Aas; Hatzoglou, Constantinos; Khalid, Muhammad Zeeshan; Vullum, Per Erik; Yan, Zewu; Bourret, Edith. (2022) Atomic-scale 3D imaging of individual dopant atoms in an oxide semiconductor. Nature Communications
Academic article
Gradauskaite, Elzbieta; Hunnestad, Kasper Aas; Meier, Quintin; Meier, Dennis; Trassin, Morgan. (2022) Ferroelectric Domain Engineering Using Structural Defect Ordering. Chemistry of Materials
Academic article

2020

Hunnestad, Kasper Aas; Roede, Erik Dobloug; Helvoort, Antonius T. J. van; Meier, Dennis Gerhard. (2020) Characterization of ferroelectric domain walls by scanning electron microscopy. Journal of Applied Physics
Academic literature review
Bak, Ohheum; Holstad, Theodor Secanell; Tan, Yueze; Lu, Haidong; Evans, Donald; Hunnestad, Kasper Aas. (2020) Observation of Unconventional Dynamics of Domain Walls in Uniaxial Ferroelectric Lead Germanate. Advanced Functional Materials
Academic article

2019

Hunnestad, Kasper Aas; Van Helvoort, Antonius. (2019) Visualizing Ferroelectric Domain Structures in ErMnO3 and Pb5Ge3O11 by Electron Microscopy. NTNU Trondheim
Masters thesis

Journal publications

Nordahl, Gregory; Jones, Lewys; Christiansen, Emil; Hunnestad, Kasper Aas; Nord, Magnus. (2023) Correcting for probe wandering by precession path segmentation. Ultramicroscopy
Short communication
Hunnestad, Kasper Aas; Das, Hena; Hatzoglou, hatzoglou; Holtz, Megan E.; Brooks, Charles M.; Van Helvoort, Antonius. (2023) 3D oxygen vacancy order and defect-property relations in multiferroic (LuFeO3)9/(LuFe2O4)1 superlattices. arXiv.org
Academic article
Hunnestad, Kasper Aas; Hatzoglou, hatzoglou; Vurpillot, F.; Nylund, Inger-Emma; Yan, Z.; Bourret, E.. (2023) Correlating laser energy with compositional and atomic-level information of oxides in atom probe tomography. Materials Characterization
Academic article
Hunnestad, Kasper Aas; Schultheiß, Jan; Mathiesen, Anders; Ushakov, Ivan; hatzoglou, constantinos; Van Helvoort, Antonius. (2023) Quantitative Mapping of Chemical Defects at Charged Grain Boundaries in a Ferroelectric Oxide. Advanced Materials
Academic article
hatzoglou, constantinos; Da Costa, Grald; Wells, Peter; Ren, Xiaochen; Geiser, Brian P; Larson, David J. (2023) Introducing a Dynamic Reconstruction Methodology for Multilayered Structures in Atom Probe Tomography. Microscopy and Microanalysis
Academic article
Hunnestad, Kasper Aas; Hatzoglou, Constantinos; Khalid, Muhammad Zeeshan; Vullum, Per Erik; Yan, Zewu; Bourret, Edith. (2022) Atomic-scale 3D imaging of individual dopant atoms in an oxide semiconductor. Nature Communications
Academic article
Gradauskaite, Elzbieta; Hunnestad, Kasper Aas; Meier, Quintin; Meier, Dennis; Trassin, Morgan. (2022) Ferroelectric Domain Engineering Using Structural Defect Ordering. Chemistry of Materials
Academic article
Hunnestad, Kasper Aas; Roede, Erik Dobloug; Helvoort, Antonius T. J. van; Meier, Dennis Gerhard. (2020) Characterization of ferroelectric domain walls by scanning electron microscopy. Journal of Applied Physics
Academic literature review
Bak, Ohheum; Holstad, Theodor Secanell; Tan, Yueze; Lu, Haidong; Evans, Donald; Hunnestad, Kasper Aas. (2020) Observation of Unconventional Dynamics of Domain Walls in Uniaxial Ferroelectric Lead Germanate. Advanced Functional Materials
Academic article

Report

Hunnestad, Kasper Aas; Van Helvoort, Antonius. (2019) Visualizing Ferroelectric Domain Structures in ErMnO3 and Pb5Ge3O11 by Electron Microscopy. NTNU Trondheim
Masters thesis

Media

3D-modeller på atomnivå lærer oss hvorfor dingser fungerer

Short promotion article for non-specialists.

2023

Poster

Hunnestad, Kasper Aas; Schulteiss, Jan; Mathisen, Anders Christian; Ushakov, Ivan; Hatzoglou, Constantinos; Van Helvoort, Antonius. (2023) Quantitative chemical analysis of charged and electronically active grain boundaries. QUOROM-8 QUOROM-8 2023-02-16 - 2023-02-16
Academic lecture

Hunnestad, Kasper Aas; Schultheiß, Jan; Mathiesen, Anders; Ushakov, Ivan; hatzoglou, constantinos; Roede, Erik Dobloug. (2023) 3D mapping of grain boundary chemistry in ferroelectrics . German Physical Association 2023 2023-03-13 - 2023-03-17
Poster

Hunnestad, Kasper Aas; Das, Hena; hatzoglou, constantinos; Holtz, Megan, E.; Brooks, Charles M.; Van Helvoort, Antonius. (2023) Quantifying charged defects in multiferroic superlattices using atom probe tomography. Ferroelectrics 2023-04-22 - 2023-04-24

2022

Academic lecture

Hunnestad, Kasper Aas; Das, Hena; Hatzoglou, Constantinos; Holtz, Megan, E.; Brooks, Charles M.; Van Helvoort, Antonius. (2022) 3D imaging of multiferroic (LuFeO3)9/(LuFe2O4)1 superlattices by atom probe tomography . German Physical Association German Physical Association 2022 , Regensburg 2022-09-04 - 2022-09-09
Academic lecture

Hunnestad, Kasper Aas; Schultheiss, Jan; Roede, Erik Dobloug; Van Helvoort, Antonius; Meier, Dennis. (2022) 3D chemical mapping of grain boundaries in polycrystalline ferroelectrics . QUOROM-7 QUOROM-7 , Online 2022-09-15 - 2022-09-15
Academic lecture

Hunnestad, Kasper Aas; Das, Hena; Hatzoglou, Constantinos; Holtz, Megan, E.; Brooks, Charles M.; Van Helvoort, Antonius. (2022) Quantifying interfacial defect accumulations in oxide superlattices. Atom probe tomography & microcsopy 2022-10-11 - 2022-10-14
Academic lecture

Hunnestad, Kasper Aas; Das, Hena; Hatzoglou, Constantinos; Holtz, Megan E.; Brooks, Charles M.; Helvoort, Antonius T. J. van. (2022) Quantifying interfacial defect accumulations in oxide superlattices. International Field Emission Society Atom Probe Tomography & Microscopy , Nanjing, China 2022-10-11 - 2022-10-14
Poster

Nordahl, Gregory; Jones, Lewys; Christiansen, Emil; Hunnestad, Kasper Aas; Nord, Magnus Kristofer. (2022) Precession segmentation to increase SPED image resolution. Ernst Ruska-Centre (ER-C) for Microscopy and Spectroscopy with Electrons PICO2022 , Netherlands 2022-05-08 - 2022-05-12
Academic lecture

Hunnestad, Kasper Aas; Das, Hena; Hatzoglou, Constantinos; Holtz, Megan, E.; Brooks, Charles M.; Van Helvoort, Antonius. (2022) Quantitative 3D imaging of oxygen defects in multiferroic (LuFeO3)9/(LuFe2O4)1 superlattices. Material research society MRS Fall Meeting , Boston 2022-11-28 - 2022-12-03
Poster

Hunnestad, Kasper Aas; Das, Hena; Hatzoglou, Constantinos; Holtz, Megan, E.; Brooks, Charles M.; Van Helvoort, Antonius. (2022) Quantifying charged defects in multiferroic superlattices using atom probe tomography. QUOROM-6 2022-03-31 - 2022-03-31
Academic lecture

Hunnestad, Kasper Aas; Hatzoglou, Constantinos; Khalid, Muhammad Zeeshan; Vullum, Per Erik; Zewu, Yan; Bourret, Edith. (2022) Atomic-Level Imaging and Quantification of Dopants in a Semiconducting Complex Oxide. Material research society MRS spring meeting 2022-05-10 -

2021

Academic lecture

Hunnestad, Kasper Aas; Hatzoglou, Constantinoss; Van Helvoort, Antonius; Meier, Dennis. (2021) Atomic-scale analysis of individual dopants in a functional oxide. German Physical Association 2021-09-28 -
Academic lecture

Hunnestad, Kasper Aas; Hatzoglou, Constantinoss; Khalid, Muhammad Zeeshan; Vullum, Per Erik; Zewu, Yan; Bourret, Edith. (2021) 3D analysis of dopants in a multiferroic oxide by atom probe tomography. Norwegian Nanosymposium 2021-10-05 -
Poster

Hunnestad, Kasper Aas; Hatzoglou, Constantinoss; Khalid, Muhammad Zeeshan; Vullum, Per Erik; Yan, Zewu; Bourret, Edith. (2021) Detection of Individual Dopants in a Semiconducting Functional Oxide. Atom probe tomography & microcsopy 2021-09-28 -

2019

Poster

Hunnestad, Kasper Aas; Schultheiß, Jan; Holstad, Theodor S.; Van Helvoort, Antonius; Meier, Dennis. (2019) Nanoscale chemical mapping in 3D by atom probe tomography: Needle preparation. Nano@NTNU Norwegian Nanosymposium , Trondheim 2019-10-16 - 2019-10-18

Språkvelger

Kasper Aas Hunnestad