A5070128690- Arctic and Antarctic ice dynamics
- Cryospheric studies and observations
- Winter Sports Injuries and Performance
- Icing and De-icing Technologies
- Climate change and permafrost
- Landslides and related hazards
- Mine drainage and remediation techniques
- Semiconductor Quantum Structures and Devices
- Groundwater and Isotope Geochemistry
- Freezing and Crystallization Processes
- Geochemistry and Geologic Mapping
- Quantum and electron transport phenomena
- Interdisciplinary Research and Collaboration
- Fatigue and fracture mechanics
- Advancements in Semiconductor Devices and Circuit Design
- Fire effects on concrete materials
- Seismic Waves and Analysis
- High-Velocity Impact and Material Behavior
University of Otago
2015-2020
University of Bristol
2018
Summary Electron backscatter diffraction (EBSD) on ice is a decade old. We have built upon previous work to select and develop methods of sample preparation analysis that give >90% success rate in obtaining high‐quality EBSD maps, for the whole surface area (potentially) low porosity (<15%) water samples, including very fine‐grained (<10 μm) large (up 70 mm by 30 mm) samples. present explain two new removing frost providing damage‐free EBSD: pressure cycle sublimation ‘ironing’. In...
Abstract Polycrystalline ice weakens significantly after a few percent strain, during high homologous temperature deformation. Weakening is correlated broadly with the development of crystallographic preferred orientation (CPO). We deformed synthetic polycrystalline at −5°C under uniaxial compression, while measuring ultrasonic P wave velocities along several raypaths through sample. Changes in measured ( V p ) and calculated from microstructural measurements CPO (by cryo‐electron...
Abstract. The elastic and anelastic properties of ice are interest in the study dynamics sea ice, glaciers, sheets. Resonant ultrasound spectroscopy allows quantitative estimates these aids calibration active passive seismic data gathered field. quality factor Q laboratory-manufactured polycrystalline isotropic cores decrease (reversibly) with increasing temperature, but compressional-wave speed attenuation prove most sensitive to indicative pre-melting ice. This method resonant can be...
Abstract Despite the importance of grounding zone sedimentation for ice sheet stability and history, evidence sedimentary deposits beneath West Antarctica's modern remains sparse. Seismic surveying shows that Kamb Ice Stream has no detectable deposit. As deposition relies strongly on flow, absence a deposit suggests transition from stream to shelf moved after stagnation Stream. Further support recent occupation comes satellite imagery sub‐ice channel features likely originated at previous...
Abstract. The elastic and anelastic properties of ice are interest in the study dynamics sea ice, glaciers sheets. Resonant ultrasound spectroscopy allows quantitative estimates these aids calibration active passive seismic data gathered field. constants attenuation constant man-made polycrystalline isotropic cores decrease (reversibly) with increasing temperature. All vary temperature, but especially compressional-wave speed prove sensitive to indicative pre-melting ice. This method...
Spin effects in III-V semiconductor quantum dot devices are being exploited both 'classical' photonic (such as spin VCSELs and an additional label communication systems) classical devices. The modelling formalisms for the two regimes often very different due to high temperature (room temperature) regime of former low (milli-Kelvin) latter. In this talk we unite approaches into a simpler formalism investigate similarities.Model expressions spin-orbit interaction (SOI) obtained. resulting form...