Julie Karel

Development of hard X-ray photoelectron SPLEED-based spectrometer applicable for probing of buried magnetic layer valence states

Publisher: Elsevier BV

Date: 08-2016

DOI: 10.1016/J.ELSPEC.2016.05.001

Magnetic properties and Curie temperatures of disordered Heusler compounds:Co1<

Publisher: American Physical Society (APS)

Date: 14-07-2016

DOI: 10.1103/PHYSREVB.94.024418

Observation of topological Hall effect in Mn₂RhSn films

Publisher: IOP Publishing

Date: 12-08-2016

DOI: 10.1088/1367-2630/18/8/085007

Influence of nanoscale order–disorder transitions on the magnetic properties of Heusler compounds for spintronics

Publisher: Royal Society of Chemistry (RSC)

Date: 2017

DOI: 10.1039/C7TC01241A

Abstract: Modifications in nanoscale chemical order can tune the magnetic properties of Co 2 FeSi x Al 1−x , indicating disorder as a potential engineering tool.

Structural, electronic, and magnetic properties of perpendicularly magnetised Mn₂RhSn thin films

Publisher: IOP Publishing

Date: 08-04-2015

DOI: 10.1088/0022-3727/48/16/164008

SARS-CoV-2 Gamma and Delta Variants of Concern Might Undermine Neutralizing Activity Generated in Response to BNT162b2 mRNA Vaccination

Publisher: MDPI AG

Date: 15-04-2022

DOI: 10.3390/V14040814

Abstract: The Delta variant raised concern regarding its ability to evade SARS-CoV-2 vaccines. We evaluated a serum neutralizing response of 172 Italian healthcare workers, three months after complete Comirnaty (BNT162b2 mRNA, BioNTech-Pfizer) vaccination, testing their sera against viral isolates of Alpha, Gamma and Delta variants, including 36 subjects with a previous SARS-CoV-2 infection. We assessed whether IgG anti-spike TRIM levels and serum neutralizing activity by seroneutralization assay were associated. Concerning Gamma variant, a two-fold reduction in neutralizing titres compared to the Alpha variant was observed, while a four-fold reduction of Delta virus compared to Alpha was found. A gender difference was observed in neutralizing titres only for the Gamma variant. The serum s les of 36 previously infected SARS-CoV-2 in iduals neutralized Alpha, Gamma and Delta variants, demonstrating respectively a nearly three-fold and a five-fold reduction in neutralizing titres compared to Alpha variant. IgG anti-spike TRIM levels were positively correlated with serum neutralizing titres against the three variants. The Comirnaty vaccine provides sustained neutralizing antibody activity towards the Alpha variant, but it is less effective against Gamma and even less against Delta variants.

Electron-Mediated Ferromagnetic Behavior inCoO/ZnOMultilayers

Publisher: American Physical Society (APS)

Date: 20-02-2013

DOI: 10.1103/PHYSREVLETT.110.087206

Formation of a Stable Surface Oxide in MnBi₂Te₄ Thin Films

Publisher: American Chemical Society (ACS)

Date: 20-01-2022

DOI: 10.1021/ACSAMI.1C19089

Abstract: Understanding the air stability of MnBi

Using structural disorder to enhance the magnetism and spin-polarization in Fe_xSi_{1 −x}thin films for spintronics

Publisher: IOP Publishing

Date: 03-04-2014

DOI: 10.1088/2053-1591/1/2/026102

Excess Specific Heat in Evaporated Amorphous Silicon

Publisher: American Physical Society (APS)

Date: 28-03-2013

DOI: 10.1103/PHYSREVLETT.110.135901

Amorphous Dielectric Thin Films with Extremely Low Mechanical Loss

Publisher: Walter de Gruyter GmbH

Date: 04-2015

DOI: 10.1515/AMM-2015-0059

Abstract: The ubiquitous low-energy excitations are one of the universal phenomena of amorphous solids. These excitations dominate the acoustic, dielectric, and thermal properties of structurally disordered solids. One exception has been a type of hydrogenated amorphous silicon ( a -Si:H) with 1 at.% H. Using low temperature elastic and thermal measurements of electron-beam evap-orated amorphous silicon ( a -Si), we show that TLS can be eliminated in this system as the films become denser and more structurally ordered under certain deposition conditions. Our results demonstrate that TLS are not intrinsic to the glassy state but instead reside in low density regions of the amorphous network. This work obviates the role hydrogen was previously thought to play in removing TLS in a -Si:H and favors an ideal four-fold covalently bonded amorphous structure as the cause for the disappearance of TLS. Our result supports the notion that a -Si can be made a “perfect glass” with “crystal-like” properties, thus offering an encouraging opportunity to use it as a simple crystal dielectric alternative in applications, such as in modern quantum devices where TLS are the source of dissipation, decoherence and 1/f noise.

Probing the electronic states of high-TMR off-stoichiometric Co2MnSi thin films by

Publisher: American Physical Society (APS)

Date: 17-03-2014

DOI: 10.1103/PHYSREVB.89.125116

Evidence for in-plane tetragonal c-axis in MnxGa1–x thin films using transmission electron microscopy

Publisher: Elsevier BV

Date: 03-2016

DOI: 10.1016/J.SCRIPTAMAT.2015.11.019

Enhanced magnetization and anisotropy in Mn-Ga thin films grown on LSAT

Publisher: AIP Publishing

Date: 30-10-2017

DOI: 10.1063/1.5004594

Abstract: Epitaxial thin films of MnxGa1−x (x = 0.70, 0.74) grown on single crystal (LaAlO3)0.3(Sr2TaAlO6)0.7 [LSAT] substrates exhibit an enhanced magnetic moment and magnetic anisotropy in comparison to films of the same composition grown epitaxially on SrTiO3 [STO] single crystal substrates. Atomic and magnetic force microscopy revealed films exhibiting uniform grains and magnetic domain structures, with only minor differences between the films grown on different substrates. High resolution transmission electron microscopy on the x = 0.74 s le grown on LSAT showed a well-ordered, faceted film structure with the tetragonal c-axis oriented out of the film plane. Further, misfit dislocations, accommodating the lattice mismatch, were evidenced at the film/substrate interface. The out of plane c lattice parameter is larger for all x in the films grown on LSAT, due to the smaller substrate lattice parameter compared to STO. The increase in c generates a larger distortion of the tetragonal lattice which promotes the enhanced magnetization and magnetocrystalline anisotropy. These results indicate that LSAT is a promising substrate for realizing highly tailored magnetic properties for future spintronic applications not only in MnxGa1−x but also in the broader class of tetragonal Mn-Z-Ga (Z = transition metal) materials.

MnxGa1−x nanodots with high coercivity and perpendicular magnetic anisotropy

Publisher: Elsevier BV

Date: 11-2016

DOI: 10.1016/J.APSUSC.2016.07.029

Two-level systems in evaporated amorphous silicon

Publisher: Elsevier BV

Date: 10-2015

DOI: 10.1016/J.JNONCRYSOL.2015.06.020

Nanocrystalline (Fe,Co,Ni)86B14 soft magnetic alloys prepared by ultra-rapid annealing

Publisher: Elsevier BV

Date: 05-2022

DOI: 10.1016/J.JALLCOM.2021.162544

Large anomalous Hall effect driven by a nonvanishing Berry curvature in the noncolinear antiferromagnet Mn ₃ Ge

Publisher: American Association for the Advancement of Science (AAAS)

Date: 04-2016

DOI: 10.1126/SCIADV.1501870

Abstract: A large anomalous Hall effect is observed in the triangular antiferromagnet Mn 3 Ge arising from an intrinsic electronic Berry phase.

Scaling of the anomalous Hall effect in lower conductivity regimes

Publisher: IOP Publishing

Date: 06-2016

DOI: 10.1209/0295-5075/114/57004

Enhanced spin polarization of amorphous Fe

Publisher: American Physical Society (APS)

Date: 27-06-2018

DOI: 10.1103/PHYSREVMATERIALS.2.064411

Hydrogen-Free Amorphous Silicon with No Tunneling States

Publisher: American Physical Society (APS)

Date: 08-07-2014

DOI: 10.1103/PHYSREVLETT.113.025503

Chemical Synthesis and Characterization of γ-Co₂NiGa Nanoparticles with a Very High Curie Temperature

Publisher: American Chemical Society (ACS)

Date: 15-10-2015

DOI: 10.1021/ACS.CHEMMATER.5B02227

Effect of chemical order on the magnetic and electronic properties of epitaxial off-stoichiometryF

Publisher: American Physical Society (APS)

Date: 06-04-2015

DOI: 10.1103/PHYSREVB.91.144402

Unexpected dependence of the anomalous Hall angle on the Hall conductivity in amorphous transition metal thin films

Publisher: American Physical Society (APS)

Date: 04-11-2020

DOI: 10.1103/PHYSREVMATERIALS.4.114405

Light-induced metastability in pure and hydrogenated amorphous silicon

Publisher: IOP Publishing

Date: 10-2015

DOI: 10.1209/0295-5075/112/26001

Evidence for localized moment picture in Mn-based Heusler compounds

Publisher: Royal Society of Chemistry (RSC)

Date: 2015

DOI: 10.1039/C5CP04944J

Abstract: The Mn magnetic moment in positions with octahedral symmetry is localized and comprised completely by itinerant electrons.

Dramatic grain refinement and magnetic softening induced by Ni addition in Fe B based nanocrystalline soft magnetic alloys

Publisher: Elsevier BV

Date: 05-2020

DOI: 10.1016/J.SCRIPTAMAT.2020.02.020

Size-dependent structural and magnetic properties of chemically synthesized Co-Ni-Ga nanoparticles

Publisher: Springer Science and Business Media LLC

Date: 06-05-2017

DOI: 10.1007/S12274-017-1554-Y

Hard x-ray photoemission study of near-Heusler Fex

Publisher: American Physical Society (APS)

Date: 09-05-2011

DOI: 10.1103/PHYSREVB.83.195112

Corrigendum to “Evidence for in-plane tetragonal c-axis in MnxGa1–x thin films using transmission electron microscopy” [Scr. Mater. 114 (2016) 165–169]

Publisher: Elsevier BV

Date: 07-2016

DOI: 10.1016/J.SCRIPTAMAT.2016.03.025

Distinct local electronic structure and magnetism for Mn in amorphous Si and Ge

Publisher: American Physical Society (APS)

Date: 14-10-2010

DOI: 10.1103/PHYSREVB.82.165202

Transparent conducting oxide induced by liquid electrolyte gating

Publisher: Proceedings of the National Academy of Sciences

Date: 19-09-2016

DOI: 10.1073/PNAS.1611745113

Abstract: Highly conducting transparent oxides are widely used as electrodes in various electronic devices where optical transparency through a low-resistance electrode is needed. Here, we show that highly conducting transparent oxide films can be formed by electrolyte gating of thin films of tungsten oxide, WO 3 , that are initially insulating. Optical and electronic structure measurements show that the films are transparent in the visible spectrum before gating, due to the significant electronic band gap of ∼3.0 eV. No significant change in the band gap is found on gating the films to the metallic state so that the films remain transparent in the visible spectral region. Thus electrolyte gating of insulating oxides is a means of obtaining new classes of transparent conducting electrodes.

Distinct Electronic Structure of the Electrolyte Gate-Induced Conducting Phase in Vanadium Dioxide Revealed by High-Energy Photoelectron Spectroscopy

Publisher: American Chemical Society (ACS)

Date: 02-06-2014

DOI: 10.1021/NN501724Q

Abstract: The development of new phases of matter at oxide interfaces and surfaces by extrinsic electric fields is of considerable significance both scientifically and technologically. Vanadium dioxide (VO2), a strongly correlated material, exhibits a temperature-driven metal-to-insulator transition, which is accompanied by a structural transformation from rutile (high-temperature metallic phase) to monoclinic (low-temperature insulator phase). Recently, it was discovered that a low-temperature conducting state emerges in VO2 thin films upon gating with a liquid electrolyte. Using photoemission spectroscopy measurements of the core and valence band states of electrolyte-gated VO2 thin films, we show that electronic features in the gate-induced conducting phase are distinct from those of the temperature-induced rutile metallic phase. Moreover, polarization-dependent measurements reveal that the V 3d orbital ordering, which is characteristic of the monoclinic insulating phase, is partially preserved in the gate-induced metallic phase, whereas the thermally induced metallic phase displays no such orbital ordering. Angle-dependent measurements show that the electronic structure of the gate-induced metallic phase persists to a depth of at least ∼40 Å, the escape depth of the high-energy photoexcited electrons used here. The distinct electronic structures of the gate-induced and thermally induced metallic phases in VO2 thin films reflect the distinct mechanisms by which these states originate. The electronic characteristics of the gate-induced metallic state are consistent with the formation of oxygen vacancies from electrolyte gating.

Tunable structural and magnetic properties of chemically synthesized dual-phase Co₂NiGa nanoparticles

Publisher: Royal Society of Chemistry (RSC)

Date: 2016

DOI: 10.1039/C6TC01757F

Abstract: The chemically tuned structural and magnetic properties of dual-phase Co 2 NiGa shape memory Heusler nanoparticles.

Monash University

Location: Australia

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Discovery Projects - Grant ID: DP200102477

Start Date: 08-2020

End Date: 07-2024

Amount: $235,000.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP220103783

Start Date: 12-2022

End Date: 12-2025

Amount: $423,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE230100065

Start Date: 07-2023

End Date: 07-2024

Amount: $1,310,536.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE200100197

Start Date: 07-2020

End Date: 12-2021

Amount: $1,102,947.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE180100054

Start Date: 2018

End Date: 12-2021

Amount: $824,080.00

Funder: Australian Research Council

ARC Centres Of Excellence - Grant ID: CE170100039

Start Date: 06-2017

End Date: 06-2024

Amount: $33,400,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE200100174

Start Date: 11-2020

End Date: 12-2022

Amount: $425,000.00

Funder: Australian Research Council