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Facilities and Shops
Atomic Hydrogen Beam Facility
This atomic hydrogen beam facility consists of an rf discharged cell, a
differential pumping system, and a host of beam density monitors inside
an ultrahigh vacuum system. The density of the hydrogen beam is about
10-8 Torr. Atomic hydrogen is created by a rf discharge and are guided
and transported by a Teflon tubing to a specific location, such as an ion
trap, to study the state select electron capture process.
Optical coating thin film facility
Thin solid films for optical and electronic applications are deposited from
the vapor phase inside the stainless steel bell jar vacuum chamber. The
material to be deposited is either evaporated from an electrically heated
container, or sputtered from a target by argon ion impact in a RF excited
plasma. The pumps for evacuating the chamber are below the bell jar, and
the evaporation and sputtering power supplies and controls are in the
cabinet beside the vacuum system.
Tau Cluster
The tau cluster (part of which is shown), consisting of 23 fast CPUs with individual memories, is
networked to perform isolated or concurrent computation.
The cluster is used to carry out path-integral and variational/diffusion
quantum Monte Carlo studies of various novel materials, including hydrogen
molecules in a host matrix, light elemental solids under high pressure,
and quantum many-body systems, such as quantum dots, boson clusters,
and helium-4 in a porous host material.
These studies are aimed to answer fundamental questions, such as which
material is the best for a hydrogen storage unit, what happens at high
pressure to light elemental solids, or how coherence and correlation manifest
themselves in an interacting quantum system in generating unusual quantum
phases such as a supersolid.
Material Preparation and Synthesis Facility
The glove box shown here is used for maintaining an inert atmosphere for
various polymeric samples, as well as preparation of other samples
throughout the department. Since the materials studied here are hydroscopic,
the samples must be kept extremely dry during preparation, storage, and
during experimentation. The system shown here provides an environment inside
the glove box which has a water content below 10ppm which is accomplished by
implementing a nitrogen gas atmosphere, along with a molecular sieve to trap
remaining water molecules. Inside the glove box is a collection of sample
preparation equipment, temperature regulation devices, equipment to monitor
sample characteristics, as well as the ability to make viscometry
measurements without exposing the samples to the environment.
Pulsed Tunable Dye Laser Facility
This facility consists of two pulsed Lambada Physik Excimer lasers which
drive three separate tunable dye lasers. The band width of each dye laser
is about 1 MHZ. These dye lasers are synchronized by an optical delay with
time resolution of a few nanoseconds. Fast optical detectors are used to
synchronize a series of events. This facility ahs been used to study the
expansion dynamics of laser induced plasmas.
Student Electronic Shop
Found in this shop are multiple stations with soldering irons, power supplies,
function generators, oscilloscopes, and various other test equipment. Many
analog and digital IC's are stocked for breadboarding circuits. Facilities
exist to make printed circuit boards for low noise and high speed designs.
There is an electrical engineer on staff to answer questions and to design
custom equipment as needed.
Ion Beam Facility
John Farley's laboratory has a laser beam/ion beam spectrometer. In this
instrument, a laser bam is used to measure the absorption spectrum of
molecular ions. Measuring the spectrum of an ion is like taking the
fingerprint of the ion: it allows identification of the ion. Furthermore,
the spectrum reveals the energy levels of the ion, the spacing of the atoms,
and the strength of the chemical bonds. Molecular ions are important in
the upper atmosphere (ionosphere), in molecular clouds in the interstellar
medium and also in industrial plasmas such as those used to make computer
chips.
Ion Trap Facility
This ions storage facility is primarily designed and fabricated in house.
The key component of this facility is a radio frequency ion trap with
cylindrical electrode and two flat end caps. The ion trap is operated
inside a stainless steel ultra high vacuum chamber that routinely maintains
a vacuum well below 10-10 Torr by a Varian turbo molecular pump in
combination with a Leybold mechanical pump. Ions are produced by laser
ablation of solid target material. Nearly all low charged state ions can
be produced, cooled and stored in the rf trap. This facility is currently
used to store multiply charged ions that are of interest to astrophysics
and fusion plasmas. Studies of these ions include the metastable state
lifetime of multiply charged ions, electron capture by multiply charged
ions, and dynamics of molecular formation at low temperatures.
H2 Cluster
The H2-cluster is purchased from a grant from US Department of Energy to
support research on Hydrogen Fuel Cells and Storage Technology project at UNLV.
The purpose of the research project is to develop a fundamental understanding of
interaction of atomic and molecular hydrogen with materials pertinent to the
storage and use of hydrogen, thus enabling improved conceptual development,
design and testing of storage options, fuel cells, and hydrogen combustion
applications.
The project emphasizes fundamental research at the atomic and molecular levels
to understand the mechanisms of hydrogen adsorption/desorption from potential
storage materials, catalysis of hydrogen adsorption and dissociation on
platinum surfaces (fuel cell applications) and rate co-efficient for atomic and
molecular hydrogen interactions in both thermal and non-thermal populations
(hydrogen combustion applications).
The cluster is made up of 19 nodes each of which has 2 dual-core Opteron processors, 16GB of RAM and 2 fast SCSI hard drives. They are networked using gigabit ethernet. The cluster is used by faculty in the Department of Chemistry and the Department of Physics.
Physical Properties Measurement System (PPMS)
The PPMS is a multi purpose system to determine the thermodynamic
properties of materials. When making new materials, it is imperative to
characterize the samples, and determining the thermodynamic properties is
often the first step. The PPMS can be used to measure specific heat, AC/DC
magnetization and AC/DC electric transport. All of these measurements are
performed in the cryostat at the left of the picture (with the yellow
warning label) which contains a superconducting magnet immersed in liquid
helium at 4 K. All measurements can be performed in applied magnetic fields
as large as 9 T and temperature as low as 0.35 K. The other equipment shown
is the various electronics required for the measurements and the computer
for automated control of the experiments.
Nonlinear optical spectroscopy facility
This facility is being used to study the photochromic bacterial protein
bacteriorhodopsin. A photochemical material changes color when it absorbs
light. In this experiment, lasers at one or more selected light
wavelengths illuminate the sample and measure the resulting changes in the
state of the sample. The photochromism in bacteriorhodopin is interesting
for optical signal processing applications since it is fast, reversible and
can be modulated by changing temperature and other experimental conditions.
Professional Glass Shop
In the foreground is a glass working lathe and in the background is a glass
annealing oven. The glass shop is also equipped with glass blowing torches
and tools, glass tubing and rod, diamond saws and drills, a grinding and
polishing machine, and a clean air bench.
Professional Electronic Shop
The College of Science has a technician on staff to assist faculty and
students. If needed, the technician can trouble-shoot equipment in the
lab if the equipment can't be brought to the shop. Many common parts are
stocked to speed repair services. The technician is also available to
explain how equipment functions and help in the selection of new equipment.
Raman Scattering Facility for High Pressure Research
Study of materials at high pressure is accomplished using this custom Raman
spectrometer. Samples are illuminated using any of the characteristic lines
produced by a Spectra Physics 2060-8S BeamLok argon ion CW laser. Light
scattered by the sample is collected and focused into a Jobin-Yvon-Spex
(JY) Ramanor U-1000 double monochromator (1 m focal length with two 1800
lines/mm holographically ruled gratings). The resulting wavelength
dispersed light can then be analyzed by a liquid nitrogen cooled JY
Spectrum 1 down-looking CCD camera (256x1024 pixels) or by a
water/thermoelectrically cooled Hamamatsu R943-02 head-on photomultiplier tube.
Reflection Time of Flight Mass Spectrometry Facility
This mass spectrometer is designed and fabricated in house. Multiply charged
ions are produced by a pulsed Nd YAG laser. These laser produced ions are
initially accelerated by an electric field into a field-free drift tube where
ions of the same q/m bundle in space. The spatial spread of the ions, due
to the initial plasma temperature, is significantly reduced by reflecting
the ions 174 degrees into a field free reflection drift tube. Our recent
study includes the charge transfer of carbon monoxide to highly stripped
oxygen and carbon ions. These studies are essential to the understanding
of X-ray emission in cometary atmospheres.
Ruby Fluorimeter Facility for High Pressure Research
This instrument indirectly measures pressure by measuring changes in
the fluorescence spectra of ruby crystals. The excitation source is a
404 nm CW diode laser. Excitation light is brought to the sample via a
series of beam splitters, mirrors and multimode optical fiber (to
facilitate future remote use). Sample alignment and location is
accomplished through the use of a white-light source, a Panasonic video
camera and a custom built Newport three dimensional remotely controlled
translational platform. Ruby emission is collected, filtered and analyzed
using a second multimode optical fiber connected to a 0.75 m Acton 750i
single monochromateor equipped with a 1200 lines/mm grating and a Princeton
Instruments 5 stage thermoelectrically cooled CCD camera (512x2048 pixels).
Dynamic Laser Light Scattering Facility
Shown here is one of the many large frame continuous wavelength ion lasers
used throughout the department. Specifically, this model is a Kr-Ion laser
manufactured by Coherent, resting on an air cushioned optical grade table.
The optical table separates the system from external vibrations, which
proves to be necessary when conducting measurements that are extremely
sensitive to external motions of any sort. Also shown (front right) is
a goniometer manufactured by Brookhaven Inc. used to conduct various laser
light scattering techniques. The primary function of the goniometer
manufactured by Brookhaven Inc. used to conduct various laser light
scattering techniques. The primary function of the goniometer allows
experiments in photon correlation spectroscopy (PCS) to be conducted.
This equipment not only houses the sample cell and proves excellent
temperature control, but allows the user to select precise scattering
angels for measurement which are essential when performing these PCS
measurements. These measurements provide information as to the size,
shaper and overall dynamics of macromolecules both in and out of solutions.
Also shown (back right) is a laminar flow clean bench which provides a dust
free environment to work in. This bench is used for a wide variety of
tasks which range from preparation and cleaning of the various optics used
in the laboratory, to sample preparation.
Professional Machine shop
The Physics Research and Development Shop provide daily support in the
following disciplines.
Solid modeling engineering design (SolidWorks CAD); fabrication of
state-of-the art prototype parts and equipment; supervise and instruct
undergraduate and graduate students and postdoctoral fellows in the
conceptualization, engineering design, and fabrication of experimental
devices, apparatus, and equipment to be used in research. Modify,
troubleshoot, repair, calibrate and maintain equipment, devices and
apparatus (e.g. vacuum systems, lasers, optical devices, telescopes)
used in research as well as in instructional laboratories and
demonstrations. This work is an integral part of a team of physicists
engaged in the following research.
High pressure Science and Engineering Center (HiPSEC), design and fabricate
apparatus that are used to build up the spectroscopic, x-ray diffraction,
and diamond-anvil cell capabilities and machine small intricate parts.
Condensed Matter Laboratory.
Non-linear Optics Laboratory.
Ion Storage Facility.
Macromolecular Systems Laboratory.
Laser Spectroscopy Laboratory.
Welding Area
There are two welding areas; one in the R&D Shop and the other in the
Student Machine Shop. Students that wish hands on experience in welding
processes are advised to be trained in the Student Shop before welding
occurs on actual parts.
High Resolution Laser Spectroscopy Facility
The Farley laboratory has a visible ring dye laser. This intense source
of narrowband tunable radiation has enabled exquisitely sensitive experiments
that would have been impossible otherwise. The dye laser has a frequency
that is defined to a precision of parts per billion. The Farley laboratory
used this apparatus to make the first measurement of the visible absorption
spectrum of the H2O + ion, the water cation.
Student Machine Shop
Students are encouraged to utilize the Student Machine Shop (after proper
instruction) to machine and assemble parts related to their research project.
16-inch Photometric Telescope
This is a 16-inch computer-operated photometric training telescope
mounted on the roof of the Bigelow Physics Building with computer
workstations dedicated to digital processing of astronomical images.
The department is part of the NASA Nevada Space Grant Consortium and a
four-college consortium that operates an automated telescope on Mt.
Hopkins, near Tucson, Arizona. UNLV researchers have observing time on
major telescopes such as Kitt Peak National Observatory. They also have
direct access to data from the Hubble Space Telescope.
Diamond Anvil Cell/X-ray Diffraction Facility for high pressure research
Pictured here is a High Pressure 2-axis diffractometer. Inside the radiation
enclosure are the Rigaku UltraX-18kW x-ray diffraction techniques are to
obtain lattice structures from both single crystal and powder samples. The
entire system is computer automated to allow for precise timed exposures
and for rapid data reduction/analysis.
Pictured here is a Merrill-Vassett diamond anvil cell mounted on top of a
multi-axis goniometer head. These cells have the capability of bringing
powder and single crystal samples to pressures upward of 100Kbar. Theses
high pressures are attained by applying torque to three symmetrically placed
screws on the face of the cell. Diamonds having culet diameter of about
250 micron are mounted in the cell in a symmetric fashion to compress
gasketed samples to a desired pressure. Images of a samples' lattice
structure at high pressure allows for the study of where different phase
transitions occur.
Cosmology Computing Cluster
The Cosmology Computing Cluster consists of 4 nodes, each of which
has 4 cores (Opteron 2.4 GHz), 8GB of memory, and 750 GB of storage
disk (total 16 processors, 32 GB of memory, and 3TB of disks).
It is used by Prof. Nagamine's
group to simulate large-scale structure of the universe and
galaxy formation processes using cosmological hydrodynamic codes.
Simulations start from early universe (redshift z~100) with
initial conditions that are consistent
with the observations of cosmic microwave background radiation, and
follow the time evolution of matter (both dark matter and gas)
distribution until the present time using the laws of gravity and
hydrodynamics. The box sizes range from 10 mega parsecs to 1 giga
parsecs, and particle numbers up to (256)^3. For larger sized
simulations, resources at national supercomputer centers are used.
One of the primary focuses of current research is the feedback
effects of supernovae and black holes on galaxy formation and damped
Lyman-alpha systems. For visualization products from simulations,
see here.
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