Browsing by Author "Hester, JR"
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- Item18O isotope substitution on the multiferroic compound DyMnO3(Australian Institute of Physics, 2013-02-06) Narayanan, N; Li, F; Hutchison, WD; Reynolds, NM; Rovillain, P; Ulrich, C; Hester, JR; McIntyre, GJ; Mulders, AMNot available
- Item2nd Asia-Oceania Instrument Scientist Workshops, Manly, July 19, 2015(Taylor & Francis Online, 2015-11-17) Hester, JR; Holt, SA; Imperia, P; Piltz, RO; Rehm, C; Rule, KC; Mole, RA; McIntyre, GJNo abstract available
- ItemCharacterisation of embedded nano-precipitates by x-ray diffraction imaging and small-angle x-ray scattering(InderScience Publishers, 2014) Pelliccia, D; Andrei, YN; Kirby, N; Hester, JRWe report on the characterisation of embedded Al2Cu nanoparticles in Al matrix by X-ray diffraction imaging and small-angle X-ray scattering. We employed direct retrieval of the average morphological characteristics of the nanoparticles from their diffraction pattern. Data suggest the possibility of acquiring truly 3D information with X-ray diffraction imaging. Validation of the results obtained with small-angle X-ray scattering is reported. © 2020 Inderscience Enterprises Ltd.
- ItemCircularly polarized soft x-ray diffraction study of helical magnetism in hexaferrite(American Physical Society, 2010-03-01) Mulders, AM; Lawrence, SM; Princep, AJ; Staub, U; Bodenthin, Y; García-Fernández, M; Garganourakis, M; Hester, JR; Macquart, RB; Ling, CDMagnetic spiral structures can exhibit ferroelectric moments as recently demonstrated in various multiferroic materials. In such cases the helicity of the magnetic spiral is directly correlated with the direction of the ferroelectric moment and measurement of the helicity of magnetic structures is of current interest. Soft x-ray resonant diffraction is particularly advantageous because it combines element selectivity with a large magnetic cross-section. We calculate the polarization dependence of the resonant magnetic x-ray cross-section (electric dipole transition) for the basal plane magnetic spiral in hexaferrite Ba0.8Sr1.2Zn2Fe12O22 and deduce its domain population using circular polarized incident radiation. We demonstrate there is a direct correlation between the diffracted radiation and the helicity of the magnetic spiral. © 2010, American Physical Society
- ItemClosing the data gap: creating an open data environment(Elsevier, 2014-02) Hester, JRPoor data management brought on by increasing volumes of complex data undermines both the integrity of the scientific process and the usefulness of datasets. Researchers should endeavour both to make their data citeable and to cite data whenever possible. The reusability of datasets is improved by community adoption of comprehensive metadata standards and public availability of reversibly reduced data. Where standards are not yet defined, as much information as possible about the experiment and samples should be preserved in datafiles written in a standard format. © 2013, Elsevier B.V.
- ItemComparing results of X-ray diffraction, µ-Raman spectroscopy and neutron diffraction when identifying chemical phases in seized nuclear material, during a comparative nuclear forensics exercise(Springer Nature, 2018-01-24) Rondahl, SH; Pointurier, F; Ahlinder, L; Ramebäck, H; Marie, O; Ravat, B; Delauney, F; Young, EL; Blagojevic, N; Hester, JR; Thorogood, GJ; Nelwamondo, AN; Ntsoane, TP; Roberts, SK; Holliday, KSThis work presents the results for identification of chemical phases obtained by several laboratories as a part of an international nuclear forensic round-robin exercise. In this work powder X-ray diffraction (p-XRD) is regarded as the reference technique. Neutron diffraction produced a superior high-angle diffraction pattern relative to p-XRD. Requiring only small amounts of sample, µ-Raman spectroscopy was used for the first time in this context as a potentially complementary technique to p-XRD. The chemical phases were identified as pure UO2 in two materials, and as a mixture of UO2, U3O8 and an intermediate species U3O7 in the third material. © The Author(s) 2018. This article is an open access publication.
- ItemThe crystal and magnetic structures of LaCa2Fe3-xMxO8 (M=Al, Ga, In)(Elsevier, 2012-06-27) Goossens, DJ; Henderson, LSF; Trevena, S; Hudspeth, JM; Avdeev, M; Hester, JRLaCa2Fe3O8 (A3B3O8) is an example of a layered structure in that it consists of pairs of octahedral, perovskite-like layers alternating with a single tetrahedral layer. This work explores the doping of non-magnetic group 13 elements, M=Al, Ga and In, onto the B-site of LaCa2Fe3−xMxO8 as a function of x. The structural and magnetic effects are examined using a combination of neutron and X-ray diffraction. Solubility limits are established. It is found that for M=Ga the solubility limit occurs between x=1.0 and x=1.25, for the synthesis conditions used, while there is evidence for low ( x < 0.25 ) but non-zero substitution of Al. Structural refinements at x=1 suggest that Ga prefers neither the tetrahedral nor octahedral sites. The magnetic structure of LaCa2Fe2GaO8 has been examined using neutron diffraction at 3.2 K and room temperature. At low temperature the staggered moment per Fe3+ is 3.8 ( 1 ) μ B in LaCa2Fe3O8 and 4.8 ( 1 ) μ B in LaCa2Fe2GaO8. The magnetic space group (P2b21′ma′) and moment direction (along c) does not appear to change with Ga substitution. © 2012, Elsevier Ltd.
- ItemCrystal structure, optical properties, and electronic structure of calcium strontium tungsten oxynitrides CaxSr1-xWO2N(American Chemical Society, 2013-09-12) Yashima, M; Fumi, U; Nakano, H; Omoto, K; Hester, JRNovel calcium strontium tungsten oxynitrides CaxSr(1-x)WO(2)N (x = 0.25 and 0.5) have been synthesized. The crystal and electronic structures, electron-density distribution, and optical properties of CaxSr(1-x)WO(2)N and CaxSr(1-x)WO(2)N (x = 0, 0.25, and 0.5) have been investigated by neutron, synchrotron, and X-ray powder diffraction; transmission electron microscopy energy-dispersive spectroscopy (TEMEDS); scanning electron microscopy; UV visible reflectance measurements; and ab initio density functional theory (DFT)based calculations. Precursor materials CaxSr(1-x)WO(2)N (x = 0, 0.25, 0.5, and 1) with a scheelite-type structure were prepared by solid-state reactions, and heated at 900 degrees C for 5 h under an ammonia flow. The main phase in the product for the composition x = 1 was metallic tungsten W, whereas cubic Pm3m perovskite-type oxynitrides CaxSr(1-x)WO(2)N were obtained for the compositions x = 0, 0.25, and 0.5. The unit-cell parameter a of the cubic perovskite-type CaxSr(1-x)WO(2)N obtained from the Rietveld analysis of synchrotron X-ray and neutron powder diffraction data decreases with an increase of Ca concentration x (0 < x < 0.5), which indicates the substitution of Ca for Sr. The existence of nitrogen in CaxSr(1-x)WO(2)N was confirmed by (I) the refined occupancy factor in the Rietveld analysis of neutron data and (2) EDS. The maximum-entropy-method electron-density analysis combined with the DFT calculations indicates W N and W-O covalent bonds in CaxSr1_xWO2N, which are formed by the overlapping of W 5d and anion 2p orbitals. The minimum electron density at the W N bond is higher than that at the W-0 one, which indicates that the W N bond is more covalent due to the smaller difference in the electronegativity between W and N atoms compared to the W and O ones: The oxidation number of W in CaxSr(1-x)WO(2)N was estimated to be 5.2 by bond valence sum, which indicates the W5+ ion with the 5di electron configuration. Precursor oxides Ca Sr,,WO, with W6* having the 5cl electron configuration are white and insulating, whereas the CaxSr(1-x)WO(2)N oxynitrides with the W5* ion having the 5di configuration are black and exhibit metallic character. These results indicate the insulator metal transition from the d oxide CaxSr(1-x)WO(2)N to the di oxynitride CaxSr(1-x)WO(2)N. © 2013, American Chemical Society.
- ItemCrystal structures and phase transitions in Sr doped Ba2InTaO6 perovskites(Academic Press INC Elsevier Science, 2013-10-01) Zhou, QD; Tan, TY; Kennedy, BJ; Hester, JRThe crystal structures of the double perovskites of the type Ba2-xSrxInTaO6 have been studied by synchrotron X-ray and neutron powder diffraction methods. The structures are based on ordered array of the tilted InO6 and TaO6 octahedra, with the Ba/Sr cations being completely disordered. The structure evolves from cubic to monoclinic Fm (3) over barm(x similar to 0) (6)-> I4/m(x similar to 1.2)-> I2/m(x similar to 1.6)-> P2(1)/n. The changes in the symmetry induced by replacing the Ba with Sr have been identified by a symmetry-mode analysis. Variable temperature S-XRD studies of selected examples have shown that heating the samples induces the same sequence of transitions observed in the composition dependent studies. © 2013, Elsevier Ltd.
- ItemCrystallographic and magnetic structure study in SrCoO3-x by high resolution x-ray and neutron powder diffraction(Australian Institute of Physics, 2016-02-04) Chang, FF; Reehuis, M; Hester, JR; Avdeev, M; Xiang, F; Wang, X; Seidel, J; Ulrich, CTransition metal oxides (TMOs) represent a wide set of materials with a broad range of functionalities, including superconductivity, magnetism, and ferroelectricity, which can be tuned by careful choice of parameters such as strain, oxygen content, and applied electric and magnetic fields. This tunability makes TMO’s ideal candidate materials for use in developing novel information and energy technologies and SrCoO3 provides a particularly interesting system for investigation due to its propensity to form oxygen-vacancy-ordered structures as the oxygen content is decreased. The ties between structural and functional properties of this material are obvious as it undergoes simultaneously structural and magnetic phase transitions between two topotactic phases: from a ferromagnetic perovskite phase at SrCoO3.0 to the antiferromagnetic brownmillerite SrCoO2.5. In this study we have determined their crystallographic and magnetic structures of SrCoO2.50, SrCoO2.875, and cubic SrCoO3.00 using high resolution X-ray and neutron powder diffraction from 4 K to 600 K. The correct structure of oxygen-deficient end-member SrCoO2.5 was determined in space group of Imma, instead of Pnma or Ima2 proposed previously, with G-type antiferromagnetic order up to TN = 570 K. In SrCoO2.875, clear peak splitting was observed from (200) in cubic phase to (004) and (440) in tetragonal phase, indicating that the precise structure is I4/mmm with a = b = 10.829(9) Å and c = 7.684(2) Å at 95 K, and the corresponding magnetic structure is ferromagnetic with 1.86(4) μB per formula, in accordance to a spin configuration of cobalt ions with an intermediate spin state of both on Co3+ and on Co4+. The end member SrCoO3.00 possesses a simple cubic crystal structure with a = 3.817(2) Å at 95 K, and ferromagnetic order up to 280 K. The magnetic moment of 1.96(8) μB /Co4+ corresponds to an intermediate spin state of Co4+.
- ItemDefect structure and property consequence when small Li+ ions meet BaTiO3(American Physical Society, 2020-08-31) Narayanan, N; Lou, Q; Rawal, A; Lu, T; Liu, Z; Chen, J; Langley, J; Chen, H; Hester, JR; Cox, N; Fuess, H; McIntyre, GJ; Li, G; Yu, DH; Liu, YIn the present work the longstanding issue of the structure and dynamics of smaller ions in oxides and its impact on the properties was investigated on 7% Li-doped BaTiO3. The investigation combined several techniques, notably neutron powder diffraction (NPD), nuclear magnetic resonance (7Li-NMR), electron paramagnetic resonance (EPR), electron microprobe, electric polarization (EP) measurement, and electronic structure calculations based on density-functional theory (DFT). Electron microprobe confirmed multiple phases, one containing incorporated Li in the BaTiO3 host lattice and another glassy phase which breaks the host lattice due to excessive Li accumulation. While the average structure of Li in BaTiO3 could not be determined by NPD, 7Li-NMR revealed one broad “disordered” and multiple “ordered” peaks. Local structure models with different defect types involving Li+ were modeled and the corresponding chemical shifts (δ) were compared with experimental values. It is found that the closest defect model describing the ordered peaks, is with Ti4+ being replaced by four Li+ ions. The biexponential behavior of the spin-lattice relaxation of the ordered peaks each with a short and a long relaxation discloses the existence of paramagnetic ions. Finally, EPR revealed the existence of the paramagnetic ion Ti3+ as a charge-transfer defect. DFT calculations disclosed local antipolar displacements of Ti ions around both types of defect sites upon insertion of Li+. This is in accordance with the experimental observation of pinching effects of the EP in Li-doped BaTiO3. These studies demonstrate the huge impact of the local structure of the doped smaller/lighter ions on the functional properties of oxides. ©2020 American Physical Society
- ItemDefect structure-property correlations in Li doped BaTiO3(Australian Institute of Nuclear Science and Engineering (AINSE), 2020-11-11) Narayanan, N; Lou, Q; Rawal, A; Lu, T; Liu, Z; Chen, J; Langley, J; Chen, H; Hester, JR; Cox, N; Fuess, H; McIntyre, GJ; Li, G; Yu, DH; Liu, Y; Li, GIn the present work we investigate the important issue of the structure and dynamics of smaller ions in oxides and the resulting impact on its functional properties. For this purpose, we selected a 7% Li-doped BaTiO3. Li is a vital ingredient in novel energy storage technologies such as Li-ion batteries. The smaller Li-ion can influence the structural stability, homogeneity, local environment, and dynamic behavior of the host lattice, affecting and optimizing the dielectric and multiferroic properties of novel polar functional materials [1-2]. However, the Li-ion positions and dynamics in functional materials are not completely understood, controversially discussed and are the subject of extensive ongoing research [3]. Furthermore, sample inhomogeneity due to Li migration to the grain boundary and/or development of multiple phases complicates the elucidation of the structure-property correlations that may lead to incorrect interpretations [4]. The selection of BaTiO3 as the host lattice is due to materials based on this being considered as the alternative to the piezoelectric lead zirconate titanate, citing environmental issues [5]. BaTiO3 also crystallizes in a simple perovskite structure and Li ions can be effectively doped into it at lower doping levels. Very recently, field-dependent electric polarization measurements on BaTiO3 exhibited a polarization–electric field double hysteresis loop upon Li doping [4]. These drastic changes to the electric polarization, related to the doping poses a good test case for the investigation of the Li induced defect structure model and its influence on the functional properties. To elucidate the above structure-property correlations, we combined several techniques, such as neutron powder diffraction electron microprobe associated with the wavelength-dispersive spectroscopy, 7Li nuclear magnetic resonance spectroscopy (NMR), electron paramagnetic resonance (EPR), electric polarization measurement, and theoretical calculations based on density functional theory [6].
- ItemDetailed investigations of phase transitions and magnetic structure in Fe(iii), Mn(ii), Co(ii) and Ni(ii) 3,4,5-trihydroxybenzoate (gallate) dihydrates by neutron and x-ray diffraction(Royal Society of Chemistry, 2011-06-28) Saines, PJ; Yeung, HHM; Hester, JR; Lennie, AR; Cheetham, AKThe effect of cation valency on the complex structures of divalent and trivalent transition metal gallates has been examined using a combination of neutron and synchrotron X-ray powder diffraction, single-crystal X-ray diffraction and XANES spectroscopy. In the divalent frameworks, M(C7H4O5)[middle dot]2H2O (M = Mn, Co and Ni), it was found that charge balance was achieved via the presence of protons on the meta-hydroxyl groups. It was also established that these compounds undergo a discontinuous phase transition at lower temperatures, which is driven by the position of the extra-framework water molecules in these materials. By contrast, in the trivalent Fe gallate, Fe(C7H3O5)[middle dot]2H2O, it was found that the stronger bonding between the meta-hydroxy oxygen and the cations leads to a weakening of the bond between this oxygen and its proton. This is turn is thought to lead to stronger hydrogen bonding with the extra-framework water. The lattice water is disordered in the Fe(iii) case, which prevents the phase transition found in the M(ii) gallates. Refinement against the neutron diffraction patterns also revealed that the relatively mild microwave synthesis of gallate frameworks in D2O led to an extensive deuteration of the ortho-hydrogen sites on the aromatic ring, which may suggest a more versatile method of deuterating aromatic organics. The antiferromagnetic structure of Co gallate has also been determined. © 2011, Royal Society of Chemistry
- ItemDimer-mediated cooperative mechanism of ultrafast-ion conduction in hexagonal perovskite-related oxides(American Chemical Society, 2023-11-14) Sakuda, Y; Murakami, T; Avdeev, M; Fujii, K; Yasui, Y; Hester, JR; Hagihala, M; Ikeda, Y; Nambu, Y; Yashima, MOxide-ion and proton conductors have found diverse applications such as in electrolytes of solid-oxide, proton-conducting, and hybrid-ion fuel cells. Research of fuel cells with higher energy efficiency at lower operating temperature has stimulated the search for ion conductors and improved the understanding of the ion-diffusion mechanism. Ion conduction in hexagonal perovskite-related materials is rare, and the mechanism of ion diffusion is unclear. Herein, we report high oxide-ion and proton conductivity (bulk conductivities in wet air: 11 and 2.7 mS cm-1 at 537 and 326 °C, respectively), high chemical, and electrical stability in a new hexagonal perovskite-related oxide Ba7Nb3.8Mo1.2O20.1. Total direct current conductivity at 400 °C in wet air of Ba7Nb3.8Mo1.2O20.1 was 13 times higher than that of Ba7Nb4MoO20. We also report a unique dimer-mediated cooperative mechanism of the high oxide-ion conduction of Ba7Nb3.8Mo1.2O20.1 (bulk conductivities in dry air: 10 mS cm-1 at 593 °C and 1.1 mS cm-1 at 306 °C). Ab initio molecular dynamics (AIMD) simulations, neutron-diffraction experiments at 800 °C, and neutron scattering length density analyses of Ba7Nb3.8Mo1.2O20.1 indicated that the excess oxygen atoms are incorporated by the formation of both 5-fold coordinated (Nb/Mo)O5 monomer and its (Nb/Mo)2O9 dimer with a corner-sharing oxygen atom and that the breaking and reforming of the dimers lead to the high oxide-ion conduction in the oxygen-deficient BaO2.1 c′ layer. The long distance between Nb/Mo and Ba cations sandwiching the c′ layer of Ba7Nb3.8Mo1.2O20.1 was found to be responsible for its low activation energy for oxide-ion conduction, leading to high conductivity at low temperatures. AIMD simulations showed that high proton conduction can be attributed to proton migration in the hexagonal close-packed BaO3 layers of Ba7Nb3.8Mo1.2O20.1. The present findings hold a great promise for the development and design of ion conductors. Copyright © 2023 The Authors. Published by American Chemical Society.
- ItemDirect synthesis of chromium perovskite oxyhydride with a high magnetic-transition temperature(Wiley Online Library, 2014-09-22) Tassel, C; Goto, Y; Kuno, Y; Hester, JR; Green, MA; Kobayashi, Y; Kageyama, HWe report a novel oxyhydride SrCrO2H directly synthesized by a high-pressure high-temperature method. Powder neutron and synchrotron X-ray diffraction revealed that this compound adopts the ideal cubic perovskite structure equation image with O2−/H− disorder. Surprisingly, despite the non-bonding nature between Cr 3d t2g orbitals and the H 1s orbital, it exhibits G-type spin ordering at TN≈380 K, which is higher than that of RCrO3 (R=rare earth) and any chromium oxides. The enhanced TN in SrCrO2H with four Cr-O-Cr bonds in comparison with RCr3+O3 with six Cr-O-Cr bonds is reasonably explained by the tolerance factor. The present result offers an effective strategy to tune octahedral tilting in perovskites and to improve physical and chemical properties through mixed anion chemistry. © 2014, Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
- ItemECHIDNA: a decade of high resolution neutron powder diffraction at OPAL(Australian Institute of Nuclear Science and Engineering (AINSE), 2018-11-19) Avdeev, M; Hester, JRThe ECHIDNA high-resolution neutron powder diffractometer at the 20MW OPAL research reactor produces high-quality data for a broad spectrum of crystal and magnetic structural studies. The poster presents an overview of the current status of the hardware, latest developments in data reduction software, statistics of the instrument usage and user programme, and instrument limitations. © The Authors.
- ItemECHIDNA: a decade of high-resolution neutron powder diffraction at OPAL(International Union of Crystallography, 2018-12-01) Avdeev, M; Hester, JRThe ECHIDNA high-resolution neutron powder diffractometer at the 20 MW OPAL research reactor in Australia produces high-quality data for a broad spectrum of crystal and magnetic structural studies. The paper presents an overview of the current status of the hardware, latest developments in data-reduction software, statistics on instrument usage and the user programme, and instrument limitations. © International Union of Crystallography
- ItemEffects of 18O isotope substitution in multiferroic RMnO3 (R = Tb, Dy)(Australian Institute of Physics, 2016-02-05) Graham, PJ; Narayanan, N; McIntyre, GJ; Hutchison, WD; Ulrich, C; Reynolds, N; Rovillain, P; Hester, JR; Kimpton, JA; Yethiraj, M; Pomjakushina, E; Condor, K; Kenzelmann, MMultiferroic materials demonstrate desirable attributes for next-generation multifunctional devices as they exhibit coexisting ferroelectric and magnetic orders. In type-II multiferroics, coupling exists that allows ferroelectricity to be manipulated via magnetic order and vice versa, offering potential in high-density information storage and sensor applications. Despite extensive investigations into the subject, questions of the physics of magnetoelectric coupling in multiferroics remain, and competing theories propose different mechanisms. The aim of this investigation was to study changes in the statics and dynamics of structural, ferroelectric and magnetic orders with oxygen-18 isotope substitution to shine light into the coupling mechanism in multiferroic RMnO3 (R=Tb, Dy) systems. We have performed Raman spectroscopy on 16O and 18O-substituted TbMnO3 single crystals. Oxygen-18 isotope substitution reduces all phonon frequencies significantly. However, specific heat measurements determine no changes in Mn3+ (28 and 41 K) magnetic phase transition temperatures. Pronounced anomalies in peak position and linewidth at the magnetic and ferroelectric phase transitions. While the anomalies at the sinusoidal magnetic phase transition (41 K) are in accordance to the theory of spin-phonon coupling, further deviations develop upon entering the ferroelectric phase (28 K). Furthermore, neutron diffraction measurements on 16O and 18O-substituted DyMnO3 powders show structural deviations at the ferroelectric phase transition (17 K) in the order of 100 fm in the b direction. The Pbnm space group is centrosymmetric and therefore does not allow ferroelectricity via atomic displacements, however our Reitveld analysis for the subgroup P21 shows significant displacements and polarisation along b that is comparable to the experimental value, making it the most promising candidate for ionic displacement induced polarisation in DyMnO3. These combined results demonstrate that structure is an important consideration in the emergence of ferroelectricity in these materials.
- ItemEffects of 18O isotope substitution in multiferroic RMnO3 (R=Tb, Dy)(Australian Institute of Physics, 2015-02-02) Graham, PJ; Narayanan, N; Reynolds, NM; Li, F; Rovillain, P; Bartkowiak, M; Hester, JR; Kimpton, JA; Yethiraj, M; Pomjakushina, E; Conder, K; Kenzelmann, M; McIntyre, GJ; Hutchison, WD; Ulrich, CMultiferroic materials demonstrate desirable attributes for next-generation multifunctional devices as they exhibit coexisting ferroelectric and magnetic orders. In type-II multiferroics, coupling exists that allows ferroelectricity to be manipulated via magnetic order and vice versa, offering potential in high-density information storage and sensor applications. Despite extensive investigations into the subject, questions of the physics of magnetoelectric coupling in multiferroics remain, and competing theories propose different mechanisms. The aim of this investigation was to study changes in the statics and dynamics of structural, ferroelectric and magnetic orders with oxygen-18 isotope substitution to shine light into the coupling mechanism in multiferroic RMnO3 (R=Tb, Dy) systems. We have performed Raman spectroscopy on 16O and 18O-substituted TbMnO3 single crystals. Oxygen-18 isotope substitution reduces all phonon frequencies significantly. However, specific heat measurements determine no changes in Mn3+ (28 and 41 K) magnetic phase transition temperatures. Pronounced anomalies in peak position and linewidth at the magnetic and ferroelectric phase transitions are seen. While the anomalies at the sinusoidal magnetic phase transition (41 K) are in accordance to the theory of spin-phonon coupling, further deviations develop upon entering the ferroelectric phase (28 K). Furthermore, neutron diffraction measurements on 16O and 18O-substituted DyMnO3 powders show structural deviations at the ferroelectric phase transition (17 K) in the order of 100 fm. These results indicate that the structure is actively involved in the emergence of ferroelectricity in these materials.
- ItemEight years in the life of ECHIDNA(Australian Institute of Nuclear Science and Engineering, 2016-11-30) Avdeev, M; Hester, JRIt has been eight years since the ECHIDNA instrument was open to users. Since then, more than 500 proposals have been completed on the instrument and more than 250 papers published as a result. In addition to scientific output, the accumulated experience of running ECHIDNA also provides interesting insights into its capabilities and usage. We will present statistics of various aspects of user experiments (including counting time distribution, instrument configuration and sample environment usage), examples of pushing the instrument limits (for example smallest samples, most absorbing materials, weakest magnetic moments), and an overview of research done on the instrument and in the ECHIDNA user community.