Research Facilities
The SMRC has capabilities and expertise in both material synthesis and material characterization. An extensive collection of laboratory equipment permits the research staff to both synthesize new materials and measure their properties in-house, facilitating research by allowing prompt feedback.
Material Synthesis
The primary piece of equipment in the SMRC Material Synthesis Laboratory is a Cyberstar Oxypuller 05-03 R & D Czochralski crystal growth system, sized for 50-60 mm crucibles. The system is fully computerized for optimal process control and features:
- A removable bellows, permitting use as either an open or closed growth chamber
- A dedicated cooling water system with high precision (within 0.1°F) temperature control
- High stability, compact 30 kW Huttinger MF (10 kHz range) power supply with closed loop control
- Optimized for 50-60 mm crucible diameter
Additional material synthesis equipment includes:
- A Dycor quadrupole mass spectrometer system used for real-time monitoring of crystal growth stations and annealing furnace atmospheres and volatile melt components. The system includes a Dymaxion RGA with enclosed ion source, capillary inlet manifold, compound turbomolecular pump, dry pump, and pump controller; 1-100 AMU range.
- High temperature (up to 1700°C) annealing furnaces with atmosphere control and monitoring capabilities.
- A Sartorius density determination kit for verification of composition and monitoring of phase changes.
- A Leica 6SD microscope with dual light source available for gross physical examination of samples as well as pre-growth inspection of iridium parts.
Photomicrograph of scintillating crystals under UV excitation
Photomicrographs used to document crystal surface details
- Sol-gel synthesis capabilities. For more information, view the SMRC Sol-gel poster (PDF).
Material Characterization
The Material Characterization Laboratory is equipped with instruments designed to measure scintillation, optical, and physical properties. Many measurements can be conducted at a wide range of sample temperatures. The measurement equipment includes:
- A Varian Cary 5000 UV-VIS-IR spectrophotometer for studies of electronic energy levels and optical properties. This instrument operates at wavelengths from 175 nm to 900 nm, with nitrogen purging capability in both the monochromator and sample compartments.
- A Hitachi F4500 scanning fluorescence spectrophotometer for emission and excitation measurements. This instrument measures fluorescence, phosphorescence, and luminescence in solid or liquid samples over a 200-900 nm wavelength range.
- Scintillation light yield and energy resolution measurements can be in the UV-VIS-IR wavelengths. Non-proportionality measurements can also be done with a wide range of excitation energies.
- Absolute light output measurements.
- A dedicated system is available for time-correlated single photon counting for investigation of scintillation kinetics is available; measurements can also be done at temperatures ranging from 9K to 800K.
- A system for thermoluminescence measurements is available for investigation of electron/hole trap parameters and the role of charge carriers in the scintillation process. This system includes an ARS compressor and cryostat designed for measurements in a 9K-800K temperature range, a LakeShore controller capable of precision temperature control, and an X-ray generator capable of continuous operation. For additional information, view the IEEE NSS TL poster (PDF).
Radioluminescence measurements can be done in the same temperature regime.
Research Collaborations
Additional research opprotunities through our collaborative work include:
X-ray absorption spectroscopy at Lawrence Berkeley Laboratory
Transmission electron microscopy at Oak Ridge National Laboratory
Larry Allard, High Temperature Materials Lab
Powder x-ray diffraction at Oak Ridge National Laboratory
Scott Speakman, High Temperature Materials Lab
For additional information, view he following publication (PDF): S. A. Speakman, W. D. Porter, M. A. Spurrier, C. L. Melcher, Thermal
expansion and stability of cerium-doped Lu2 SiO5, Mater. Res. Bull. 41(2) 423-435 (2006).
Journal Link: Materials Research Bulletin
