cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1920377
title: The inner workings of the earthquake cycle: New insight from microstructural & textural analysis of natural fault rocks I

description: Identification of the mechanochemical processes occurring during fault slip is of fundamental importance to understand earthquake nucleation and propagation. We will use textural analysis to explore the micromechanical processes occurring during and after slip at seismic rates utilizing an unique sample set of active fault samples from the Central Apennines, Italy, which has been subject to devastating earthquakes. These slip zones are characterized by extreme grain size reduction necessitating the textural analysis capabilities available at ISIS. Preliminary microstructural and GPS data show that brittle, seismic failure is followed by interseismic periods where crystal plasticity i.e. ductile flow may occur. Outcomes will allow us to evaluate the significance of ductile flow during the earthquake cycle and therefore advance our understanding of fault dynamics and seismic hazard.
DOI: 10.5286/isis.e.rb1920377-1
title: The inner workings of the earthquake cycle: New insight from microstructural & textural analysis of natural fault rocks I

description: Identification of the mechanochemical processes occurring during fault slip is of fundamental importance to understand earthquake nucleation and propagation. We will use textural analysis to explore the micromechanical processes occurring during and after slip at seismic rates utilizing an unique sample set of active fault samples from the Central Apennines, Italy, which has been subject to devastating earthquakes. These slip zones are characterized by extreme grain size reduction necessitating the textural analysis capabilities available at ISIS. Preliminary microstructural and GPS data show that brittle, seismic failure is followed by interseismic periods where crystal plasticity i.e. ductile flow may occur. Outcomes will allow us to evaluate the significance of ductile flow during the earthquake cycle and therefore advance our understanding of fault dynamics and seismic hazard.
DOI: 10.5286/isis.e.rb1920499-1
title: Exploration of possible spin-charge ordered phases in La2-xBaxCoO4 (x=1/3 and 1/2)

description: This is a proposal to measure the magnetic spectrum of single crystal La2-xBaxCoO4 for the first time. The isostructural layered cobaltates with Sr and Ca instead of Ba have been studied extensively. The x=1/2 composition exhibits long-range checkerboard charge order and accompanying antiferromagnetic order, but the x = 1/3 composition is more complex. It has a nanoscale coexistence of different electronic phases, including period-3 spin-charge stripes, and has a distinctive hourglass-shaped magnetic spectrum. The Ba-doped system has not been investigated previously. Our objective is to obtain a complete mapping in energy and momentum of the magnetic spectrum of La2-xBaxCoO4 with x = 1/3 and 1/2. The results will be compared with the known spectra of La2-xSrxCoO4, and by analysing the spectra quantitatively we hope to gain a picture of the electronic ground state in these systems.
DOI: 10.5286/isis.e.rb1920499-2
title: Exploration of possible spin-charge ordered phases in La2-xBaxCoO4 (x=1/3 and 1/2)

description: This is a proposal to measure the magnetic spectrum of single crystal La2-xBaxCoO4 for the first time. The isostructural layered cobaltates with Sr and Ca instead of Ba have been studied extensively. The x=1/2 composition exhibits long-range checkerboard charge order and accompanying antiferromagnetic order, but the x = 1/3 composition is more complex. It has a nanoscale coexistence of different electronic phases, including period-3 spin-charge stripes, and has a distinctive hourglass-shaped magnetic spectrum. The Ba-doped system has not been investigated previously. Our objective is to obtain a complete mapping in energy and momentum of the magnetic spectrum of La2-xBaxCoO4 with x = 1/3 and 1/2. The results will be compared with the known spectra of La2-xSrxCoO4, and by analysing the spectra quantitatively we hope to gain a picture of the electronic ground state in these systems.
DOI: 10.5286/isis.e.rb1920502-2
title: Doping effects in a S = 1/2 spin ladder system near quantum criticality

description: Spin ladders are excellent model systems for studying quantum phase transitions, as they exhibit a quantum critical point between non-magnetic spin singlet dimers to Néel magnetic order as inter-ladder exchange is increased. Ba2CuTeO6 is a Cu2+ S = 1/2 two-leg spin ladder system, that is close to the quantum critical point on the Néel ordered side. We have prepared the solid solution Ba2CuTe1-xWxO6 in an attempt to tune magnetic interactions past the quantum critical point. We will use muon spin rotation and relaxation to investigate the ground state of these materials. This will allow us to determine whether we have tuned the system to quantum criticality, or whether the materials remain magnetically ordered.
DOI: 10.5286/isis.e.rb1920502-8
title: Doping effects in a S = 1/2 spin ladder system near quantum criticality

description: Spin ladders are excellent model systems for studying quantum phase transitions, as they exhibit a quantum critical point between non-magnetic spin singlet dimers to Néel magnetic order as inter-ladder exchange is increased. Ba2CuTeO6 is a Cu2+ S = 1/2 two-leg spin ladder system, that is close to the quantum critical point on the Néel ordered side. We have prepared the solid solution Ba2CuTe1-xWxO6 in an attempt to tune magnetic interactions past the quantum critical point. We will use muon spin rotation and relaxation to investigate the ground state of these materials. This will allow us to determine whether we have tuned the system to quantum criticality, or whether the materials remain magnetically ordered.
DOI: 10.5286/isis.e.rb1920644
title: Muon Studies of Ion Diffusion in Single-Crystal Photovoltaic Materials

description: In recent years, the family of lead halide perovskite materials (e.g. MAPbI3) has attracted substantial interest due to their unique combination of properties and potential solar cell, light-emitting diode, and laser applications. One of the issues with these materials is to keep high efficiency during operation i.e. life-time problems. One of the main reasons behind such degradation has been identified as ion-diffusion causing inhomogeneities in the chemical composition, especially at surfaces and interfaces within the device. This proposed project aims to study the true intrinsic Iodine and Bromine ion diffusion process in high-quality single crystalline samples of MAPbI3 and MAPPbBr3 using our own developed muon spin rotation (muSR) technique. The study is an initial study on the course towards future in situ / in operando studies using the same (and similar) single crystal samples.
DOI: 10.5286/isis.e.rb1920644-1
title: Muon Studies of Ion Diffusion in Single-Crystal Photovoltaic Materials

description: In recent years, the family of lead halide perovskite materials (e.g. MAPbI3) has attracted substantial interest due to their unique combination of properties and potential solar cell, light-emitting diode, and laser applications. One of the issues with these materials is to keep high efficiency during operation i.e. life-time problems. One of the main reasons behind such degradation has been identified as ion-diffusion causing inhomogeneities in the chemical composition, especially at surfaces and interfaces within the device. This proposed project aims to study the true intrinsic Iodine and Bromine ion diffusion process in high-quality single crystalline samples of MAPbI3 and MAPPbBr3 using our own developed muon spin rotation (muSR) technique. The study is an initial study on the course towards future in situ / in operando studies using the same (and similar) single crystal samples.
DOI: 10.5286/isis.e.rb1920644-2
title: Muon Studies of Ion Diffusion in Single-Crystal Photovoltaic Materials

description: In recent years, the family of lead halide perovskite materials (e.g. MAPbI3) has attracted substantial interest due to their unique combination of properties and potential solar cell, light-emitting diode, and laser applications. One of the issues with these materials is to keep high efficiency during operation i.e. life-time problems. One of the main reasons behind such degradation has been identified as ion-diffusion causing inhomogeneities in the chemical composition, especially at surfaces and interfaces within the device. This proposed project aims to study the true intrinsic Iodine and Bromine ion diffusion process in high-quality single crystalline samples of MAPbI3 and MAPPbBr3 using our own developed muon spin rotation (muSR) technique. The study is an initial study on the course towards future in situ / in operando studies using the same (and similar) single crystal samples.
DOI: 10.5286/isis.e.rb1900139
title: SER Measurement 2019

description: Soft error rate measurements will be conducted by means of high energy neutron irradiation on electronic devices.
DOI: 10.5286/isis.e.rb1900139-1
title: SER Measurement 2019

description: Soft error rate measurements will be conducted by means of high energy neutron irradiation on electronic devices.
DOI: 10.5286/isis.e.rb1910046-2
title: Cobalt phase analysis and internal strain under thermomechanical loading: allotropic transformation study

description: The present proposal leans on the study of the elastoviscoplastic behavior of a polycrystalline Co by neutron diffraction (ENGIN-X) in line with theoretical investigations : 4 dogbone-shaped samples will be charged in situ under incremental tensile strain at 4 different temperatures (ambient, 400, 450 and 500°C). To obtain a consequent data set for strain analyses, {hk.l} diffraction peaks will be followed along 2 principal directions. Collected patterns will provide the necessary data to establish a reliable model to understand and predict the thermomechanical behavior of Cobalt. It will especially enable the improvement of polycrystalline plasticity models through the integration of additional phenomena such as the contribution of the different deformation mechanisms to the macroscopic behavior with temperature and allotropic transformation induced by temperature and/or plasticity.
DOI: 10.5286/isis.e.rb1920364
title: Lipid dynamics in yeast cell membranes  effect of ergosterol and its precursors

description: A cell membrane can contain hundreds of different lipid molecules, but our understanding of the dynamics of cell membranes is very limited. As a result of a collaboration between the ILL and ESS on the deuteration of lipids from cell cultures, we can now produce 100s of milligrams of lipid extracts from yeast and other microbial cell cultures, sufficient for neutron spectroscopy studies of their dynamics. We recently carried out the first QENS experiment on IRIS to probe the dynamics of the phospholipid extract from P. pastoris yeast, and found that there is a significant difference in their average molecular dynamics compared to model lipids such as POPC and DMPC. We now propose to continue our investigation on IRIS to probe the effect of ergosterol and its drug-resistance related precursors on yeast phospholipid dynamics.
DOI: 10.5286/isis.e.rb1920364-1
title: Lipid dynamics in yeast cell membranes  effect of ergosterol and its precursors

description: A cell membrane can contain hundreds of different lipid molecules, but our understanding of the dynamics of cell membranes is very limited. As a result of a collaboration between the ILL and ESS on the deuteration of lipids from cell cultures, we can now produce 100s of milligrams of lipid extracts from yeast and other microbial cell cultures, sufficient for neutron spectroscopy studies of their dynamics. We recently carried out the first QENS experiment on IRIS to probe the dynamics of the phospholipid extract from P. pastoris yeast, and found that there is a significant difference in their average molecular dynamics compared to model lipids such as POPC and DMPC. We now propose to continue our investigation on IRIS to probe the effect of ergosterol and its drug-resistance related precursors on yeast phospholipid dynamics.
DOI: 10.5286/isis.e.rb1920490
title: Probing the ground state magnetism at the local scale of an unusual metallic pyrochlore Pb2-xCdxIr2O7-d;

description: Common d5 pyrochlore iridates, A2Ir2O7 or A2Ir2O6O, are reported to have long range magnetic order based on muSR experiment. Only Pr2Ir2O7 has been identified as a metallic spin liquid. The lone d4 pyrochlore Pb2Ir2O7-d; appears different due to nonmagnetic Pb at A-site and high vacancy tolerance at O site due to Pb 6s2 lone pair. This large oxygen vacancy ensures presence of Ir4+ and Ir5+, but the susceptibility shows a paramagnet-like trend with negative theta. Moreover, the system shows a non-T2-type metallic resistivity. To tune the Ir4+ and Ir5+ ratio by controlling the vacancy content, lower sized Cd cation is doped at the Pb site (Pb2-xCdxIr2O7-d; with x=0, 0.5, 0.8) which reduces moment by increasing Ir5+ (J=0) content but the susceptibility remained similar. Hence the local magnetic structure in Pb2Ir2O7-d; and its evolution with Cd-doping will be worth investigating by muSR.
DOI: 10.5286/isis.e.rb1920490-1
title: Probing the ground state magnetism at the local scale of an unusual metallic pyrochlore Pb2-xCdxIr2O7-d;

description: Common d5 pyrochlore iridates, A2Ir2O7 or A2Ir2O6O, are reported to have long range magnetic order based on muSR experiment. Only Pr2Ir2O7 has been identified as a metallic spin liquid. The lone d4 pyrochlore Pb2Ir2O7-d; appears different due to nonmagnetic Pb at A-site and high vacancy tolerance at O site due to Pb 6s2 lone pair. This large oxygen vacancy ensures presence of Ir4+ and Ir5+, but the susceptibility shows a paramagnet-like trend with negative theta. Moreover, the system shows a non-T2-type metallic resistivity. To tune the Ir4+ and Ir5+ ratio by controlling the vacancy content, lower sized Cd cation is doped at the Pb site (Pb2-xCdxIr2O7-d; with x=0, 0.5, 0.8) which reduces moment by increasing Ir5+ (J=0) content but the susceptibility remained similar. Hence the local magnetic structure in Pb2Ir2O7-d; and its evolution with Cd-doping will be worth investigating by muSR.
DOI: 10.5286/isis.e.rb1920668
title: Determination of type-2 cycloidal ordering in BiFeO3 thin films

description: Multiferroics have recently aroused a large interest in the community, opening the route to promising applications especially in spintronics. Among multiferroics, BiFeO3 (BFO) is one of the most studied as it shows multiferroic properties at room temperature. When deposited as thin film, the bulk-like cycloidal modulation (cycloid of type 1) destabilizes and especially under tensile strain a new cycloid (cycloid of type 2) with a propagation vector along [11-2] direction takes place. The aim of this proposal is to observe such new cycloidal modulation and evidence its propagation vector and its periodicity we want to compare with data we obtained using NV magnetometry measurements.
DOI: 10.5286/isis.e.rb1920668-1
title: Determination of type-2 cycloidal ordering in BiFeO3 thin films

description: Multiferroics have recently aroused a large interest in the community, opening the route to promising applications especially in spintronics. Among multiferroics, BiFeO3 (BFO) is one of the most studied as it shows multiferroic properties at room temperature. When deposited as thin film, the bulk-like cycloidal modulation (cycloid of type 1) destabilizes and especially under tensile strain a new cycloid (cycloid of type 2) with a propagation vector along [11-2] direction takes place. The aim of this proposal is to observe such new cycloidal modulation and evidence its propagation vector and its periodicity we want to compare with data we obtained using NV magnetometry measurements.
DOI: 10.5286/isis.e.rb1920152
title: Crystal Electric Field (CEF) Effect in CeIr3Ge7 and YbIr3Ge7

description: We recently discovered new members of the stoichiometric 1-3-7 family of crystals including YbRh3Si7, YbIr3Ge7, CeIr3Ge7, and YbIr3Si7, whose magnetic and transport properties reflect large crystal electric field(CEF) anisotropy. Inelastic neutron scattering measurements on CeIr3Ge7 and YbIr3Ge7 will allow us to directly measure their CEF transitions from which we can then parameterize their single ion Hamiltonians. This analysis will definitively establish the nature of their spin anisotropies and the g-tensor of their ground state doublet, from which we can determine the size of the magnetic moment reduced by crystal field effects. Our studies thus far have revealed the importance of single ion properties in these two materials and it is thus crucial that we directly measure their CEF schemes to understand the origins of these effects.
DOI: 10.5286/isis.e.rb1920182
title: Fine structure of a confined quantum translator-rotator probed with high-resolution: HD@C60

description: A process known as molecular surgery enables the synthesis of the fullerene C60 enclosing a small molecule such as H2, H2O, HF and CH4. The caged molecules in these molecular endofullerenes are quantum rotors showing the isolation and free rotation expected in a low pressure gas, but in an easily handled form and high effective concentration. In molecular endofullerenes the energies of the quantised translational states may be measured by inelastic neutron scattering and provide a detailed test for models of non-bonding interactions.In this proposal we aim to measure the energy levels of the hydrogen isotopomer HD enclosed in C60, denoted HD@C60. HD provides advantages over H2 as the different mass of the two atoms causes substantial mixing between the rotational and translational quantum states, and all rotational states may be occupied.
DOI: 10.5286/isis.e.rb1920182-1
title: Fine structure of a confined quantum translator-rotator probed with high-resolution: HD@C60

description: A process known as molecular surgery enables the synthesis of the fullerene C60 enclosing a small molecule such as H2, H2O, HF and CH4. The caged molecules in these molecular endofullerenes are quantum rotors showing the isolation and free rotation expected in a low pressure gas, but in an easily handled form and high effective concentration. In molecular endofullerenes the energies of the quantised translational states may be measured by inelastic neutron scattering and provide a detailed test for models of non-bonding interactions.In this proposal we aim to measure the energy levels of the hydrogen isotopomer HD enclosed in C60, denoted HD@C60. HD provides advantages over H2 as the different mass of the two atoms causes substantial mixing between the rotational and translational quantum states, and all rotational states may be occupied.
DOI: 10.5286/isis.e.rb1920249
title: A crystallographic study on the quantum spin liquid candidates Cu5xZnx(VO4)2O2CsCl, x = 0, 1, 2

description: We propose to analyse the crystal structures of a new quantum (S=1/2) geometrically frustrated material based on the mineral averievite and its Zn-doped variants Zn_xCu_{5-x}Zn_x(VO_4)_2O_2CsCl, where x = 0, 1 and 2. The parent material has a magnetic lattice based on the pyrochlore slab (a kagome lattice sandwiched by two Cu^2+ hexagonal lattices) and Zn-doping on the hexagonal site is thought to form a S=1/2 kagome magnet (x=2) and a quantum spin liquid candidate. We propose to use HRPD to determine whether Zn-doping is only taking place on the Cu hexagonal lattice, and characterise the trigonal crystal structures and any weakly distorted structures.
DOI: 10.5286/isis.e.rb1920249-1
title: A crystallographic study on the quantum spin liquid candidates Cu5xZnx(VO4)2O2CsCl, x = 0, 1, 2

description: We propose to analyse the crystal structures of a new quantum (S=1/2) geometrically frustrated material based on the mineral averievite and its Zn-doped variants Zn_xCu_{5-x}Zn_x(VO_4)_2O_2CsCl, where x = 0, 1 and 2. The parent material has a magnetic lattice based on the pyrochlore slab (a kagome lattice sandwiched by two Cu^2+ hexagonal lattices) and Zn-doping on the hexagonal site is thought to form a S=1/2 kagome magnet (x=2) and a quantum spin liquid candidate. We propose to use HRPD to determine whether Zn-doping is only taking place on the Cu hexagonal lattice, and characterise the trigonal crystal structures and any weakly distorted structures.
DOI: 10.5286/isis.e.rb1920504
title: Proton Exchange Membrane Water Electrolyzer Heat Dissipation Through Porous Media

description: Investigation focuses on resolving the temperature distribution of water within porous media of electrochemical device using ToF neutron imaging technique. The temperature of the water has a great impact on the performance of the device and the heat dissipation estimation is an important factor in electrochemical cell characterization in terms of voltage loss origins. This study aims to prove that it is possible to obtain temperature gradients and possibly the map of heat distribution over the active area of the cell to identify possible hot spots which can lead to accelerated degradation. Further work might lead to development of new diagnostic technique for Fuel Cells and Electrolyzers.
DOI: 10.5286/isis.e.rb1920504-1
title: Proton Exchange Membrane Water Electrolyzer Heat Dissipation Through Porous Media

description: Investigation focuses on resolving the temperature distribution of water within porous media of electrochemical device using ToF neutron imaging technique. The temperature of the water has a great impact on the performance of the device and the heat dissipation estimation is an important factor in electrochemical cell characterization in terms of voltage loss origins. This study aims to prove that it is possible to obtain temperature gradients and possibly the map of heat distribution over the active area of the cell to identify possible hot spots which can lead to accelerated degradation. Further work might lead to development of new diagnostic technique for Fuel Cells and Electrolyzers.
DOI: 10.5286/isis.e.rb1920550
title: In Operando Diffusion Measurements on an All Solid-State Garnet Battery Cell by Muon Spin Relaxation Spectroscopy

description: The development of all-solid state batteries is of significant interest as a solid electrolyte enables the removal of the flammable solvent phase and is stable to much higher potentials than modern batteries. We wish to perform in situ measurements on two all solid-state batteries to develop our fundamental understanding of the diffusion processes that occur during cycling. The all solid-state garnet materials under investigation offer excellent structural stability, high ionic conductivities, and do not react in contact with lithium metal anode. By studying the interfacial diffusion with a structurally equivalent electrode we hope to greatly enhance our understanding of the lithium diffusion mechanisms and rates, enabling further structural modifications to enhance the beneficial properties within a future all solid-state battery.
DOI: 10.5286/isis.e.rb1920550-1
title: In Operando Diffusion Measurements on an All Solid-State Garnet Battery Cell by Muon Spin Relaxation Spectroscopy

description: The development of all-solid state batteries is of significant interest as a solid electrolyte enables the removal of the flammable solvent phase and is stable to much higher potentials than modern batteries. We wish to perform in situ measurements on two all solid-state batteries to develop our fundamental understanding of the diffusion processes that occur during cycling. The all solid-state garnet materials under investigation offer excellent structural stability, high ionic conductivities, and do not react in contact with lithium metal anode. By studying the interfacial diffusion with a structurally equivalent electrode we hope to greatly enhance our understanding of the lithium diffusion mechanisms and rates, enabling further structural modifications to enhance the beneficial properties within a future all solid-state battery.