June 2017: Science Camps
School is out. Graduation has passed. The next thing to focus on is summer camps. 19 campers joined the Village Church Science camp for the first week. One of the first stops of the week was in the physics lab to learn about experimental science. We talked about motion of particles and how that works for sound. The campers enjoyed playing with waves on strings and making noise using a speaker and function generator. Then we broadened the focus and talked about how the particles of light work.
May 2017: Wave Motion with People
As the weather is getting warm, more labs can be done outside. In the picture, Dr. Campbell is explaining the index of refraction in terms of speed on rough terrain. The Principles of Physics students are taking the place of photons and their marching speed is considerably slow than 300,000,000 m/s.
May 2017: pnp Junctions
As the quarter comes to a close, lots of activities are going on. In the Physical Electronics lab, the students have completed pnp transistors. For the last lab of the quarter we looked at them using several different microscopes. In the picture at the left, the doped areas are visible as the shiny colored areas. The boundaries between the doping are made mechanically and are visible as the gouges in the surface.
April 2017: Telescopes and Microscopes
Spring Quarter means the material we are covering in all the 200-level classes is about light. One of the labs we do is to build a simple telescope out of two lenses. The picture shows the magnified (and inverted) tree outside the lab window. Our lenses allow a magnification of about six times.
March 2017: Vibration Hunting
Our final project in Experimental Physics this quarter was to find vibrations on our vacuum system. The vacuum is created by a pump which shakes the entire system. It would be nice to reduce the vibration so we took measurements from the fan, the motor, and the compressor to see which one is responsible for the largest shaking. In the picture, the amplitude of each frequency is plotted from the motor. The peak at 29 Hz is the highest so a new motor would help us reduce the noise.
February 2017: Making Parts
In Experimental Physics we are making a motor coupling. We have made the part two different ways to see the differences (strengths and weaknesses) in the manufacturing processes. On the left of the picture are the parts that were printed using PLA on our 3D printer. On the right are the equivalent pieces that we machined from aluminum using a lathe, end mill, and drill press.
From this process, we found that the machined parts took longer to make but had better tolerances so we used them for the motor coupling.
January 2017: Circuit Boards
In Experimental Physics this quarter, we are learning about electronic components. One lab was spent learning to design circuits and building a circuit board using household items. We also sent the design for each circuit board out to a company to have professional boards made. In the picture, four of the boards are shown. Each board does the same thing but since each student designed their own board, the layout is a little different.
December 2016: Winter & Solar
This December has brought more snow to the Walla Walla valley than usual. In the picture, our solar panels are under several inches of snow. This has not been the best month for solar power generation.
November 2016: Student Research
Every two years we set aside a department chapel to highlight student research. This November 1 was that meeting. Three physics majors (Lam, Alina, and Devin) presented their research from the last year or two. We had an excellent turnout and enjoyed the breadth of research projects that students are able to do here at WWU and at our associated schools.
October 2016: Speed of Light
In the Modern Physics lab this quarter, our first experiment was to measure the speed of light using a laser and and light detector. Initially we build the detector circuit on a breadboard. That wasn't stable enough so Dr. Ekkens designed the PCB shown in the upper left of the picture. Further work in the lab suggested that the circuit could be simplified to the circuit shown on the upper right. The bare board is shown at the lower right. Results from this design are very good with the calculated speed of light being 299,000,000 m/s with an uncertainty of 11,000,000 m/s.
September 2016: Using the Observatory
The first Monday of the school year was also the first use of the observatory for this year. We had about 20 physics majors and friends look at Mars and Saturn through the small telescopes and a globular cluster through the large telescope.
August 2016: 3D Printer
This summer the physics department purchased a 3d printer kit. Over the summer, the kit was built up and the first parts have been printed. In the picture, the second piece ever is being printed. This piece is a sample stage for the PVC scanning tunneling microscope. If the piece gets used, the microscope title will need to change to PVC + PLA. The 3d printer will be used most often in the Experimental Physics classes.
July 2016: Building Equipment
Through this past spring and into the summer, we have been working on building up new equipment. During the spring quarter, one of the physics majors started working on two new electro-magnets. He cut the pieces of steel into the right lengths. During the summer, the first magnet was finished with help from Dr. Ekkens. This magnet has been built using a slightly different process than the previous ones - the pieces of steel have been welding together instead of being bolted together. Results so far look promising with over 1000 Gauss being generated at 3 amps. The second magnet has not been completed yet so physics majors during the 2016-2017 school year will work on it.
June 2016: Summer Camp
Graduation has come and gone. The summer session has started and General Physics students are taking classes each morning. The physics department helps with science camps during the summer. This summer, we hosted students on two days. In the picture at the left, the campers are looking through a microscope to see what the display on their cell phone looks like. They also played with lenses and built several circuits.
June 2016: Graduation
Graduation is here. Pictured are Dr. Liebrand at the left, Dr. Ekkens at the right, and the entire physics graduating class in the middle. In fairness, four students graduated the previous year which is higher that average for our department.
May 2016: Semiconductor Labs
As we come to the end of the quarter, the Physical Electronics laboratory does a lab were we look at several commercially available semiconductor. In the picture at the right, one of the lab groups is using the light-based microscope to get pictures of an operational amplifier. They are measuring the width of the traces that make up the activity elements of the chip.
April 2016: Building pn Junctions
In the Physical Electronics course, the students are building a pn junction (a diode). So far we have used the tube oven to heat the silicon wafer to over 1000 C to diffuse another material into the wafer. During lab in the coming weeks, we will add metal contacts and test the diode. In the picture at the left, the tube oven is nice and toasty.
March 2016: Liquid Nitrogen and LEDs
The last laboratory of the quarter for the nanotechnology class used liquid nitrogen. In the picture here, a green LED is submerged into a bath of liquid nitrogen. As it cools, the color shifts to yellow. Once the LED is removed and warms up, the color returns to the original wavelength.
February 2016: Gravitational Waves
LIGO announced their discovery of gravitational waves at a press conference in Washington DC this month. At the LIGO Hanford site, a special event was hosted to discuss the data and tour the site. Several of us associated with the Physics Department were able to attend the event. In the picture below, we are listening to the sound two black holes make as they collide.
February 2016: Using the STM
Week 5 in nanotechnology: In the first week of lab we built the scanning head for the scanning tunneling microscope, in the second week of lab we worked on the electronics and connections to the computer, and in the fourth week of lab we tested it all out. Today we starting looking a different samples included a DVD disk, copper circuit boards, and graphite. In the picture below, the leader board from the day is shown with insets of the various groups working with their microscopes. A definite spirit of competition was felt during the lab. The previous record resolution of 16 nm is history - broken by three of the four lab groups. Group four was going for the ultimate prize - trying to image graphite. It is very difficult to do in a room full of people and they didn't get today. Maybe later . . .
January 2016: Building the STM
This quarter in Introduction to Nanotechnology lab we are building a scanning tunneling microscope. During the first week of lab, we built the physical system. In the picture at right, it is the while PVC standing up in front of Martin. During the second week, we worked on the electronics and connections to the computer. The record resolution from last time is 16 nm. We are hoping to best that by the end of the month.
December 2015: The Last General Physics Lab
One lab group celebrated the last General Physics lab of the quarter with chips and party hats. They also took some data.
November 2015: Small Stage
Freshman physics major, Heidi, has been starting on student research. Her first project is to build a small translation stage. In the picture, two of the small motors are sitting on the surface where the stage will eventually be mounted. So far the work is going slowly since it is hard to get everything to fit in the available space.
October 2015: Solar Research
At Walla Walla University we do some undergraduate research in the physics department. In this picture, Alina is working on solar cells. We start with a doped silicon wafer and change the doping in a region of the wafer. Then we can test how good of a solar cell it is. So far our research focuses on making things safely rather than on making them efficient.
September 2015: Applied Physics
It is September and the school year is upon us. In this picture, senior physics and math major, Howie solves vector equations to keep his balance.
August 2015: GPU Computing
We recently acquired, with the help of the university’s academic commuting department, a Dell Precision 7910 equipped with a NVIDIA K20 Graphics Processing Unit (GPU). The K20 GPU doesn’t process graphics, it’s dedicated to general purpose processing and works in parallel with the computer’s CPU. Whereas a computer’s CPU will typically have 2, 4, 6 or more independent processing units called cores, the K20 has 2496 GPU cores. A GPU core is not as powerful as a CPU core but there’s a bunch of them and by using them in parallel, the time to complete a numerical calculation can be reduced significantly. A calculation that would have taken 3 weeks of constant calculating on a typical desktop computer will only take three days on the 7910.
Dr. Campbell and his students will use the GPU accelerated computer to study the dynamics of protein molecules in general and the protein folding problem in particular. The first molecular dynamics calculation performed on the 7910 has been animated so that the motions of the individual atoms can be seen. The animated molecule is a Lysozyme protein in water (not shown) at a temperature 300 K.
July 2015: LIGO Laser Symposium
On July 31, area colleges were invited to LIGO for a Laser Symposium. Walla Walla University sent three students and two professors to the event. The morning was devoted to talks by LIGO personnel. The afternoon had a poster session and a tour of LIGO. In the picture at the left, Rebekah, Ian, and Spencer are standing by the prototype mass holder for advanced LIGO. At the time of the visit, LIGO was six weeks away from the first advanced LIGO science run.
July 2015: Summer Class Options
This summer Dr. Campbell is teaching General Physics. The class meets all morning since a full year class is jammed into the summer. This class is taught every other summer at WWU. In the picture at the right, Dr. Campbell is explaining how a magnetic field exerts force on a moving electron.
June 2015: Whips
Normal people use whips in several applications - none of which normally occur in college. Strangely, the average whip-wielding person does not consider the physics involved. In this picture, the Classical Mechanics class is demonstrating certain principles of physics on the lawn using a massed string. To the unaided eye, it appears that students are playing with whips.
May 2015: Physics Seminar with WWU graduate
Darryl Masson, WWU graduate, returned to campus to give a talk on his research in graduate school at Purdue University. He is on the team building the largest Xenon-based dark-matter detector in the world. While most of his work is done in Indiana, the detector is buried beneath the Alps. Physics is so hard when a person has to travel to exotic locations.
April 2015: Physics Seminar with WWU graduate
Jeff Botimer, WWU graduate, returned to campus to give a talk on his research in graduate school. He entertained the audience with stories of graduate school work, mysteries of how soap works in salt water, and strange behaviors of nanofluids.
March 2015: 4-Point Probes from PVC
In the Physical Electronics lab, we use a device called a 4-Point probe to measure the resistance of a semiconductor. We own three of the commercial probes. The construction of the probe is quite simple so we have started building a similar probe in house. The first prototype is shown in the picture at the right and mostly consists of a PVC housing and four sewing needles. For the first data from this prototype, the results are very close to the commercial system.
February 2015: Thin film thickness
In several upper division labs, we deposit thin layers of metal. The common way of measuring the deposited thickness is to use a QCM meter. The QCM meter is quite is expensive so we do not own one. This winter, we have begun experimenting with ways of measure resistance during the deposition. In theory, the resistance should be related to the thickness. In the picture at the left, a microscope slide is coated with aluminum in the center. The black strips on the ends are where the wires are connected to the glass slide. As the aluminum is added to the center region, the resistance between the black strips decreases. This method will be tested during the spring quarter of Physical Electronics.
January 2015: E/M tubes
One of the hardest sections of physics for many physics students is understanding how magnetic fields work. Since students can’t see the fields, it is hard for them to visualize how the fields flow and interact with matter. The e/m Apparatus gets around some of these problems by making a stream of electronics visible. We still can’t see the fields, but we can see how the electron stream interacts with the fields. In the vacuum bulb, helium gas ionizes when electrons strike it and emits a greenish light that can be seen. Several donors have given money to help buy additional e/m hardware so that this experiment can be done in the lower division labs. In the picture at the right, the latest two purchases are shown ready for action.