The acoustic properties of trumpets have been studied thoroughly, but little to no previous work has been done regarding the acoustics of trumpet mutes. Harmon mutes have a distinctively "buzzy" sound when they are used in performance and it is the opinion of a large number of trumpet players who use Harmon mutes that they should be dented before they are used in performance. Modifications were made to several Harmon mutes by either denting them or drilling holes in them. An impedance head was used to measure the resonant frequencies of the trumpet and mute to see what effect these modifications had on the acoustics of the system. It was found that Harmon mutes have similar behavior to Helmholtz resonators, but significant deviations from this behavior were observed. If Harmon mutes are better understood, then a more informed decision as to whether or not they should be dented can be made.

Many 2 dimensional materials, such as Tungsten Diselenide (WSe₂) have many interesting device applications such as thin and flexible photo detectors and transistors. We use a process called chemical vapor deposition, which involves depositing a vapor of WSe₂ on a substrate by a specific application of heat. Specifically, we installed a secondary heating coil in our furnace which allows for a region of uniform temperature near the substrate. This modification allows for large scale growth of single crystals on the substrate. This approach to manufacturing has the advantage of allowing more samples to be studied and inevitably being more applicable to industrial applications. To determine if this method is feasible, we probe the quality of these crystals by measuring their electrical properties.

Methods to isolate and analyze single biomolecules have enabled the exploration of enzyme dynamics at incredible resolution and have revealed phenomena that cannot be observed with traditional bulk assays. For proteins like DNA helicases and polymerases, such a detailed understanding is essential to study genetic pathways like excision repair and the regulation of homologous recombination. Single molecule experiments also allow new biotechnology to be developed, such as DNA sequencers or gene editors. Despite these single molecule advances, conflicting results have been reported about biomechanical properties of UvrD helicase, including the number of nucleotides that UvrD moves per reaction step. UvrD is of particular interest given its highly conserved structure across species and its many roles in regulatory genetic processes, making it an ideal target for antibacterial drug development. We analyze UvrD using a new single-molecule technique called Single-molecule Picometer Resolution Nanopore Tweezers (SPRNT), developed at the UW nanopore lab, which has unprecedented spacial and temporal sensitivity. In SPRNT, a membrane protein pore MspA is embedded in a phospholipid bilayer, forming an electrical connection between two salt solutions. A voltage applied across the pore causes ion current to flow through. It also draws negatively charged DNA bound to UvrD into the pore. UvrD is too large to fit through MspA, and comes to rest on the rim, arresting the DNA’s motion. Different DNA nucleotides in the pore modulate the ion current. As UvrD walks along the DNA, it draws the DNA out of the pore and changes the ion current. Therefore, the durations of ion-current states are kinetic measurements of UvrD. With SPRNT we directly measure the sizes and durations of single steps taken by UvrD along DNA, which cannot be seen with any other single molecule technique and enable us to shed new light on an important enzyme.

All physical systems are ultimately governed by the laws of quantum mechanics. Over the past decades, it has become clear that these laws enable new generations of quantum information technologies that can profoundly outperform their classical counterparts. However, this depends critically on (i) the ability to efficiently entangle quantum systems (qubits) at rates much faster than the rate of quantum decoherence and (ii) the ability to scale the system with reasonable cost per added qubit.
Color centers in diamond, such as the nitrogen-vacancy (NV) center, have emerged as a promising qubit candidate. Pairs of NV centers can be entangled via the interference and detection of emitted single photons. Entanglement generation with this method was previously demonstrated in a non-scalable manner; adding additional qubits would require the costly hand-assembly of macroscopic equipment. This project aims to develop integrated circuitry for quantum information, where each macroscopic device is shrunk to an equivalent piece of photonic circuit.
Such circuits are easy to devise, but are extremely difficult to realize in the non-ideal circumstances of reality. Two main effects contribute to this difficulty: (1) the optical properties of NV centers are damaged by local imperfections in the diamond environment and (2) comparatively low fabrication precision prevents ideal production of photonic circuitry. We are developing both (a) passive and (b) active methods to mitigate these errors. This includes (1a) high temperature annealing of our diamond to reduce local defect concentration, (1b) applying electric fields to dynamically stabilize the local electro-magnetic NV environment, (2a) improving etch quality by reducing sidewall roughness and slant, and (2b) developing a wet etch to deterministically correct circuit dimensions. Further progress depends on traversing large parameter spaces to determine the optimal settings for success. Thus, automated testing procedures are being developed to make this traversal possible.

Researchers are working to determine in-depth information about the substructure of the proton. This includes the proton's fundamental charge and current distributions, described by functions called electric and magnetic form factors. These form factors have traditionally been determined by computing elastic electron-nucleon scattering cross sections, to first-order expansion in the electromagnetic fine structure constant, α_e—encompassing a process called one-photon exchange. Experimental discrepancies in the proton's electric-to-magnetic form factor ratio have prompted a need to compute cross sections to second order expansion in α_e, involving two-photon exchange (TPE) interactions. Two methods for calculating TPE cross section contributions exist: one based on hadronic degrees of freedom (suitable at low Q², where Q is the four-momentum transfer between the electron and nucleon) and the other on partonic (quark-level) degrees of freedom (applicable at high Q²). Both methods have been claimed to principally account for the form factor discrepancy. However, ambiguities exist in the separation of the parts of the cross sections independent of the underlying hadronic structure (“soft” parts) and the parts dependent on such structure (“hard” parts). We aim to resolve such ambiguities by first rederiving current quark-level calculations to better understand exactly how the hard and soft parts of the cross section are separated and the underlying physical motivations. Furthermore, we plan to compare these calculations to known behavior of the hard part of the cross section in the limit that the scattering angle goes to zero. Ultimately, our objective is to pave the way toward a unified description of TPE effects at all Q² values. Achieving this goal will further pin down the nature of the proton's interior, and the results in turn can be used to better understand the neutron and other hadrons.

Quantum information research often require lasers to deliver energy to devices and to acquire data. The goal of this project is to create an inexpensive and easy-to-build tool to measure and control laser power to support our lab’s quantum information research. The tool interfaces with our lab’s existing data collection and analysis modules. A standalone module is also present for adoption outside of our lab. Some of the intended applications of this tool are the generation of saturation curves for quantum emitters, and performing photoluminescence excitation spectroscopy on samples, both of which require precise control of laser power. The system uses a National Instruments data acquisition device to record a voltage generated by a laser power sensor. The software module also interfaces with an Arduino microcontroller, which can be used to adjust the laser’s power. The software module allows the user to set, monitor in real-time, and record laser power from a graphical user interface. The data taken utilizing the developed power controller will advance the development of quantum computation hardware based on single photons and quantum spins. Quantum computers are theoretically predicted to solve certain classes of problems that are currently unsolvable on today's computers, including the factoring of large numbers which is at the heart of current secure communication protocols.

High-powered electromagnets are used in many different fields of science such as quantum physics and synthesis chemistry. Some projects require a very strong magnetic field to work. This magnet will allow students the freedom to design complex projects that utilize a strong magnetic field However, they are generally quite expensive and only available for use at well-funded research facilities and universities. Thus, we present our research in the design and construction of a cost-effective electromagnet capable of producing a highly-uniform magnetic field that can be used to further undergraduate research at Edmonds Community College. Our principal focus is on the reduction of engineering, fabrication and maintenance costs through a novel radial-flow cooling system which can be easily 3D-printed using high-temperature plastics in conjunction with a solid Bitter-plate solenoid design, requiring far less intricate and less expensive machining processes than conventional staggered-channel Bitter-plate designs. In order to make meaningful comparisons of generated field and thermal profiles with other published designs, our design maintains general shape and structural congruence to a design by Sabulsky, et. al., yet differing significantly in the design of the cooling system. 

Diamond magnetometry enables the measurement of small-scale magnetic fields using nitrogen vacancy (NV) defect centers in diamond. Nanoscale magnetic field detection has a range of applications in biology and chemistry, such as imaging of magnetically-tagged molecules for the study of biological processes. Diamond magnetometry uses optically detected magnetic resonance (ODMR), a technique which combines radio frequency (RF) magnetic fields with optical excitation to control the defect spin. To detect DC magnetic fields, typically continuous wave RF and optical fields are used. However it is well-understood that continuous optical excitation limits the sensitivity of the technique. This project demonstrates a pulsed ODMR system executed in LabVIEW, in which optical initialization and radio-frequency spin control are staggered in time and compares the performance against the continuous wave execution. This program will enable more sensitive measurements of biological systems where orientation matters.

The nitrogen-vacancy (NV) center is a defect in diamond formed by replacing two carbon atoms by a nitrogen atom and a vacant lattice site. The NV center is a promising qubit candidate for quantum information, and its sensitivity to magnetic fields allows it to measure these fields. Due to the lattice structure of diamond, the NV center can have one of four possible orientations. For quantum information and sensing applications, control over this orientation is desirable, and would enable the production of better quality devices. Ab initio models predict that the NV orientation can be controlled through annealing, however the model depends critically on the barrier heights for defect diffusion which are difficult to calculate quantitatively. Preliminary data from our group demonstrated that heating the diamond up to high temperatures (> 1000 C) can sometimes cause single NV centers to appear, disappear, or change orientations. However, information on the frequency at which these changes occur, and thus information on barriers for diffusion, were unknown. Here we conduct thousands of single defect studies to determine these relevant rates as a function of the annealing temperature and time. While NV centers fluoresce under green laser light, restricting the polarization of this light only allows NV centers in that direction to fluoresce. By taking multiple confocal images at several polarizations, two families of orientations can be distinguished. These images are taken before and after the annealing process and then are compared using customized computer software to gather statistical data on the dynamics of single NV centers.

Nickel sulfate hexahydrate (NiSO4.6H2O) is an important industrial compound most commonly used in the nickel-plating industry. Approximately 40,000 tons are produced and consumed each year by manufacturers requiring corrosion-resistant components ranging from consumer electronics to medical devices and aerospace engineering. Freitas et. al. found that zinc sulfate heptahydrate crystal growth increased by 38% under a magnetic field of 0.3-0.7T compared to crystallization under earth’s magnetic field alone, whereas Lundager et. al. have presented evidence that paramagnetic materials such as CuSO4.5H2O do not exhibit such magnetically-induced increases in crystal growth rate. We present here our progress on confirmatory experiments aimed at fitting Nyvlt theory of cumulative crystal weight fraction M(L) and average growth rate G in batch synthesis of diamagnetic ZnSO4.7H2O and paramagnetic NiSO4.6H2O under external, uniform, homogeneous magnetic fields 0.0T<B<1.0T. Our study will examine the differences in the growth rate of paramagnetic and diamagnetic sulfate crystals under the influence of a manipulated magnetic field. Recrystallization is a method of purification during the synthesis process of many compounds. If recrystallization can be improved to increase percent yield by influencing the magnetic field surrounding the compound, it may be a profitable method for drug manufacturers to consider.

Semiconductor materials are essential components for modern electronics, making them one of the most useful tools in the modern world. In recent years, scientists have discovered single layered, two-dimensional (2D) materials that exhibit semiconducting properties. These 2D semiconductors can be used to create light emitting diodes (LEDs), field-effect transistors (FETs) and are promising candidates for a new generation of high performance solar cells. The optical response of these 2D semiconductors are highly sensitive to the crystal purity; impurities within the crystal lattice can obscure their unique optical properties. Here, we use photoluminescence spectroscopy to characterize the optical properties of tungsten diselenide (WSe2) produced using a new high pressure growth technique at the National Institute for Materials Science and Engineering in Japan. We analyze the spectrum of emitted light to determine the crystal quality and compare the degree of circular polarization in the sample photoluminescence, a key indicator of crystal quality, with other samples found in the literature. We find the sample of WSe2 to be of good quality with few impurities, making this method a step forward in the production of high quality WSe2 crystals.

Direct verifications of the validity of Newton's equations for vacuum free-fall in introductory physics laboratories are notoriously difficult due to the presence of atmospheric interactions between falling objects and their environments. The theoretical result, for example, that the gravitational acceleration of an object is independent of its mass is rather easy for observant students to experimentally reject under normal laboratory conditions. What is not so easy is to experimentally verify the validity of mass-independence in-vacuo. This is hindered by inaccessibility to vacuum environments or access to one small enough to fit in a classroom; such access is limited to organizations like NASA. We present here the construction and testing of a portable 1.5m tall extruded-acrylic vacuum free-fall apparatus designed for repeated-measures experiments of time-of-fall with a 2.5g, 40mm diameter magnetic ball over atmospheric pressure ranges 10-4 Torr < p_chamber < 760 Torr. The apparatus includes 12V electromagnet catch and release system within its all-externally-housed actuating mechanisms, automatic digital data acquisition, and a planar optical laser detection system. By comparing time trials in atmosphere and in vacuum, the difference in free-fall times will be isolated and found to be due to air resistance which is not accounted for in the original Newtonian formula. Parameters for this apparatus can be modified to test other ideas for fluid dynamics, such as coefficients of drag and the effects of fluid density on objects as they move through a fluid while using the already present vacuum environment as a control.

Analyzing complicated, extended source emissions in radio frequencies allows for going beyond typical point source models used for Epoch of Reionization analysis. Our research uses data from the Murchison Widefield Array, which is a radio telescope observing regions of the southern hemisphere to detect the faint signal from hydrogen during the formation of the first stars and galaxies. Extended source emissions can include celestial bodies ranging from active galactic nuclei emitting jets of synchrotron emission to the first galaxies that populated our universe. We anticipated the extended sources to show structural changes from day to day and in different frequencies, due to normalization errors, ionospheric disturbances, and physics of the frequency-dependent emission.We made histograms of the radio data of the extended source objects to create images in different frequencies and from different days to get a more accurate view of the extended sources. This process was also used to create difference images for direct comparison between frequencies and observations. These images can be incorporated into a formula that removes unwanted bright objects from our view of the Epoch of Reionization. We did, in fact, observe expected changes from day to day and in different frequencies, as well as observing changes that could be due to atmospheric disturbances or other potential sources of error. This has been taken into account along with the potential for improvements to normalization for the sake of comparison. The images created prove that we are statistically sampling at a higher resolution than expected due to the brightness of the extended source objects, which has important implications on our ability to work towards imaging and understanding the point just beyond the Epoch of Reionization, and from there, the early Universe.

During brain surgery for intractable epilepsy, clinicians utilize electrodes placed on the cerebral cortex to monitor seizure activity and map functional brain areas in patients so that the epileptic brain regions may be removed. This recording method is called electrocorticography (ECoG) and is essential to prevent the accidental removal of brain regions that are crucial for daily activities. To reduce tremors produced by Parkinson’s disease, electrical stimulation is applied to electrodes implanted within the deep brain near the subthalamalic nucleus. In both cases, to optimize treatment, a more detailed study of current flow during electrical stimulation than is currently done, due to surgical limitations of electrode placement, is needed. In addition, the time available to work with patients during brain surgery is extremely limited, necessitating a non-clinical research platform. I developed a saline-enriched gelatin phantom brain that mimics the electrical resistivity of the brain to study brain stimulation outside the surgery room, and I compared measurements taken with this model to analogous measurements of the brains of human patients made by my group. I found that my measurements agree within 10-15% with those made by my group on human brains. Using the phantom brain will allow us to easily and safely study electrical brain stimulation. Also, an electrical phantom that can be used offline to determine the most effective measurements will be extremely valuable to inform future research questions while working with patients. We are utilizing the phantom brain model to study how various electrode geometries and the cerebrospinal fluid layer that covers the brain have an effect on the amount of current that flows into the brain. Findings in our phantom brain will help us more effectively treat neurological disorders like intractable epilepsy and Parkinson’s and perform safer stimulations through optimized stimulation protocols.