Shared experimental facilities include Central Facilities operated by the Nebraska Center for Materials and Nanoscience (NCMN) and Shared Laboratory Facilities specific to this MRSEC. The Central Facilities are recharge centers with faculty supervisors and materials specialists who maintain equipment and train users.
The MRSEC-related Shared Laboratory Facilities are described briefly below.
A. Magnetic Characterization Facilities
David Sellmyer, Sy-Hwang Liou, Roger KirbyThese facilities allow measurements of a broad variety of magnetic and magnetooptical properties of materials and include
1) two Quantum Design SQUID magnetometers (7 T and 5.5 T),
2) Alternating Force Gradient Magnetometer,
3) Lakeshore 9T extraction magnetometer and ac susceptometer,
4) Lakeshore vibrating sample magnetometer (300 K – 1000 K),
5) two magneto-optic Kerr spectrometers, and
6) Zeiss Axiotron Kerr-effect microscope.
B. Electron Spectroscopy Facilities
Peter DowbenThese facilities permit measurements of the spin-dependent electronic band structure of surfaces and include
1) spin-polarized inverse photoemission and angle-resolved inverse photoemission facilities at Nebraska,
2) spin-polarized photoemission and angle-resolved photoemission facilities at the Louisiana Center for Advanced Microstructures and Devices synchrotron,
3) UV and soft X-ray CVD facilities, and
4) ESCA and angle-resolved XPS facilities.
C. Fast Dynamics Facility
Roger KirbyThis facility, established by the W.M. Keck Foundation, includes a Coherent Mira 900 femtosecond laser that produces 10 nJ light pulses 150 fs in length at a repetition rate of 76 MHz. The laser output can be tuned over the wavelength range 700 to 900 nm. The repetition rate can be varied from 1 kHz to 27 MHz, at up to 50 nJ pulse energy. Also available is a second harmonic generation unit, which permits the implementation of “two-color”experiments. The optical system is set up in an optical delay line “pump-probe” configuration, with the “probe” pulse being used to measure materials properties at times ranging from 1 ps to 2 ns after the perturbation. A full range of optical components is available, and dedicated optical detectors, amplifiers, choppers, etc. permit a wide variety of measurements.
D. Computational Facilities
Kirill Belashchenko, Xiao Cheng ZengBeowulf-type clusters including a 64-dual-core AMD Opteron machine and a 32-core AMD Athlon MP machine are maintained for calculations of electronic and atomic structure, spin transport, and magnetization dynamics. The computer clusters utilize high-performance communication and switching technology that allows us to perform efficient parallel computations. The available software includes state-of-the-art first-principles density functional codes, molecular dynamics, and Monte-Carlo codes, micro magnetic codes, and visualization software.
