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  Development of calcium and oxygen nanosensors for in-vivo diagnostics

  Isbell, Sydney; Mendonsa, Adrian; Cash, Kevin J.

  Diagnostic tests to determine analyte concentration can be repetitive and require extensive training for proper analysis. To address these limitations, we developed two ratiometric nanosensors (calcium (Ca2+) and oxygen (O2)) which could be implemented in-vivo to give insight into biological functions such as nerve signaling and cellular respiration. The Ca2+ nanosensors’ optical properties (fluorescence and absorbance) vary to reflect the surrounding Ca2+ concentration. These sensors are selective to Ca2+ over other biologically relevant cations (Mg2+, Na+, K+) and show a sensitivity to Ca2+ at concentrations as low as 100 µM. The O2 nanosensor is composed of two dyes encapsulated in a hydrophobic PVC matrix. The O2 sensitive dye, platinum octaethylporphyrin (PtOEP), shows a decrease in luminescence with increasing oxygen concentrations. Whereas, the reference dye, DiA, has no O2 sensitivity. These O2 sensors are reversible and have a detection range that spans from anoxic (0% O2) to atmospheric conditions (21% O2). While the Ca2+ and O2 sensors showed functionality in in-vitro studies, testing these sensors in-vivo will determine their effectiveness as a long-term diagnostic aid.
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  Harnessing geomicrobial respiration in engineered wetlands for pre-treatment of brackish waters

  Garza, Max; Gidley, Nicholas; Wang, Weishi; Yang, Zhaoxun; Vega, Michael A. P.; Vanzin, Gary; Sharp, Jonathan O.

  As arid regions become increasingly vulnerable to climate change, brackish groundwater offers the potential to supplement existing water resources, particularly for inland states such as Colorado. However, Brackish Water Reverse Osmosis (BWRO), presents a unique set of challenges that include membrane fouling due to elevated concentrations of inorganic precipitates and the production of substantial quantities of brine concentrate that often harbor heavy metal contamination. A possible mechanism for increasing BWRO efficacy is the use of shallow, unit process open water (UPOW) wetlands colonized by diatoms for biological pre-treatment. The photosynthetic diel (day/night) cycling in the wetlands, which passively increases pH during the day as carbonate is consumed, mimics traditional water treatment to create favorable, alkaline conditions needed for metal precipitation, but without chemical additions. Through various processes, the microbial mat (biomat) that naturally forms within UPOW wetlands can potentially reduce scalants (calcium, magnesium, and sulfates), as well as oxidize challenging constituents, such as arsenite, from the water prior to membrane treatment. Therefore, laboratory-scale UPOW wetlands were created using biomat harvested from an operational field-scale constructed wetland and challenged with synthetic brackish water. Preliminary results suggest that the reduction of scalant concentrations and oxidation of heavy metals can prevent excess membrane fouling and enhance RO rejection. This approach promotes environmental sustainability by eliminating the need for chemical additions, reducing brine concentrate volumes, and by decreasing energy and labor requirements. Findings may ultimately help address technoeconomic issues associated with BWRO and help guide further investigations into biological pre-treatment of brackish water.
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  Hip-belt load sharing reduces peak shoulder pressure across walking slopes during heavy load carriage

  Inge, Madeline M.; Rizeq, Hedaya N.; Slider, Amy; Sessoms, Pinata H.; Silverman, Anne K.; Sturdy, Jordan T.

  Musculoskeletal injury to the spine and lower back resulting from heavy load carriage (30–40 kg) is common among military service members. Static peak pressure is a reliable parameter for predicting discomfort. The effect of using a hip belt on shoulder pressure is not well understood. This study aimed to quantify the pressure under shoulder straps when carrying a backpack with and without a hip belt. Three military service members wore a helmet and body armor (~6.5kg) and carried a backpack in two attachment conditions: (1) entirely shoulder borne, and (2) with a hip-belt engaged, all totaling 40% body weight. Participants walked at three different slope conditions (10° downhill, level, and 10° uphill) at 1.15 m/s for each backpack condition. Peak pressure across both shoulders was extracted from each condition. Shoulder borne peak pressure (down: 36.33 kPa; level: 37.67 kPa; up: 36.67 kPa) was greater than the hip belt (down: 29.67 kPa; level: 24.67 kPa; up: 29.67 kPa). Walking with the hip belt engaged compared with the shoulder borne-only backpack resulted in ~9 kPa smaller peak shoulder pressure on average across all three slopes, indicating that peak pressure is reduced when using a hip belt, although greater participant numbers are needed to confirm these results.
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  Optimization of space nuclear reactor shielding through computational analysis

  Hoffmann, Madeline; King, Jeffrey C.

  Nuclear reactors emit ionizing radiation that can be harmful to people and electronic equipment. Shielding materials that attenuate this radiation can be a significant fraction of the mass of a space nuclear reactor power system. Optimizing space reactor shielding geometry and composition allows the design of shields that can reduce neutron and gamma-ray doses from the reactor to an acceptable using the minimum amount of shielding material. This project generated a Python 3.10 script that uses OpenMC to test arbitrary compositions of different materials in various layers and geometries to optimize a shield for space reactor applications. OpenMC is an open-source Monte Carlo-based neutron transport code that probabilistically models the movement of neutrons and photons as they interact with a user-specified environment. When finished, the program will analyze combinations of neutron absorbers (lithium hydride, enriched lithium hydride, and boron carbide) and photon absorbers (tungsten and depleted uranium) arranged in different layers and thicknesses to determine their ability to reduce dose from a hypothetical space reactor to 5 mrem/hr at a point 10 m from the surface of the payload-side of the shield. The shield will be modeled as two opposed truncated cones with a total thickness of 50 cm. The cones will be tested with in multiple configurations to determine the optimal geometry to minimize mass while meeting the target dose. Future investigations will expand the model to include total thickness optimizations and a more detailed dose analysis over a target area.
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  Backpack motion relative to the torso is affected by walking slope

  Giltinan, Kagan P.; Rizeq, Hedaya N.; Slider, Amy; Sessoms, Pinata H.; Silverman, Anne K.; Sturdy, Jordan T.

  Military backpacks are equipped with hip belts, which have been shown to support 30% of the vertical force from the backpack. These belts do not offload enough force to prevent tissue strain on the shoulders, which can lead to discomfort and injury. Stiffness and damping in a backpack’s straps and connections can affect backpack movement, which may be related to tissue strain, when walking. However, the effects of using a hip belt on relative motion between the backpack and the wearer are unclear. Four active duty military participants walked at 1.15 m/s on uphill (+10¬∞), downhill (‚àí10¬∞), and level (0¬∞) slopes. They wore body armor with helmet and backpack using only the shoulder straps (Shoulder) or with the hip belt secured (Hip Belt), carrying 40% body weight total. 3D motion of the backpack and torso was obtained with optical motion capture. Maxima and minima of backpack-torso displacement were calculated in each walking condition. The difference between sequential maxima and minima were used to obtain ranges of vertical backpack-torso displacement during each walking condition for each participant. The hip-belt did not influence relative vertical motion of the backpack. The pack and slope did affect the horizontal relative displacement (p = .086). The greatest relative displacement for anterior/posterior direction was 7.7mm, and vertical direction was 19.9mm. Horizontal displacement was not affected by slope alone during Hip Belt, but was affected during Shoulder (p = .056). The vertical relative displacement was affected by slope, p = .007.
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  Low-cost modular and flexible laser source

  Spoor, Henry; Adams, Daniel

  This project investigates the feasibility of producing high-quality, high-reliability laser beams from traditional handheld laser pointers. The goals of this project included understanding the fundamental principles and functionality of a handheld laser pointer as well as conversion of said laser pointer to a setup that could be used in a research-level capacity. To achieve these goals, handheld lasers were disassembled to their component parts, and extensive testing was performed on the maximum capabilities of the laser pointers. Data was collected on the maximum supplied current the laser diode could withstand, the viability of creating a tunable intensity laser and the potential for making a reproducible product. In the testing process, the converted laser pointers were found to be reliable if constrained to a limited current. Additionally, the laser beam was successfully made to have a tunable intensity by varying the supplied current. Additional testing will be performed to determine the lifespan of the converted laser pointer as well as the reproducibility of the project for use in a research setting.
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  Relationship between hand grip strength and mediolateral torso movement in five times sit-to-stand, The

  Beebe, Claire A.; Silverman, Anne K.; Miller, Michael F.

  Balance regulation during daily activities is a key component of movement performance and fall risk as we age. There is a well-defined correlation between lower limb muscle strength and hand grip strength (HGS) and lower limb muscle strength is critical for balance regulation. The Five Times Sit-To-Stand test (5xSTS) is an evaluation of muscle strength and mobility during transitions that helps identify individuals at risk of fall. Thus, we aimed to determine if mediolateral movement biomechanics during the 5xSTS test, which are important for balance performance, were correlated with HGS. Ten young and healthy participants completed a 5xSTS trial where they rose from the seat to a standing position and returned to the seat five consecutive times as quickly as possible. We performed a Pearson correlation analysis (α ± < 0.05) between range of mediolateral torso center of mass (COM) displacement, dominant HGS and time to completion of 5xSTS. There was not a significant correlation between time to completion and HGS (rho (ρ) = -0.515, p = 0.127). A moderate negative correlation that approached significance (0.05 < p < 0.10) was found between mediolateral torso COM displacement and HGS (rho (ρ) = -0.558, p = 0.094). There was no correlation between mediolateral torso COM displacement and time to completion (rho (ρ) = 0.143, p = 0.693). HGS could help indicate mediolateral balance performance during 5xSTS and improve the lower limb strength assessment due to its correlation with torso motion. Recording dominant HGS alongside 5xSTS completion time may provide insight into mediolateral dynamic balance performance.
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  Changes in extracellular matrix stiffness affect pancreatic islet function

  Sela, Amit; Johansen, Chelsea; Farnsworth, Nikki

  In the pancreas, the islet is surrounded by a specialized protein scaffold known as the extracellular matrix (ECM) that regulates cell survival and insulin secretion. Little is known about how the properties of the pancreas microenvironment, like matrix stiffness, regulate islet function in health and disease. Previous studies have shown that tissue stiffness in muscle cells regulates phosphofructokinase (PFK) activity. The mechanisms underlying mechanotransduction regulation of insulin secretion have not been well studied in the β-cell and a connection between metabolism and mechanotransduction has never been studied in intact islets. We hypothesize that increasing matrix stiffness will increase islet glucose sensitivity by increasing PFK activity. Our lab has developed a 3D reverse thermal gel (RTG) system that allows us to mimic the islet microenvironment and to investigate how the environment affects islet function. To determine the effect of changes in ECM stiffness on islet function we encapsulated mouse islets in the RTG with increasing stiffness as determined by rheological analysis. Glucose-stimulated insulin secretion, PFK activity, and PFK expression was measured after 24 hours of culture. We found that increasing RTG wt% yielded increasing stiffness at 40°C. Insulin secretion increased as the matrix stiffness increased in basal and high glucose conditions. Insulin secretion at high glucose normalized to low glucose (stimulation index) decreases with matrix stiffness indicating dysfunction to insulin secretion. PFK activity increased in islets encapsulated in stiffer RTGs. Our results provide insight into how changes in ECM stiffness contribute to islet dysfunction.
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  Intelligent prediction of traffic conditions via integrated data-driven crowdsourcing and learning

  Seo, Hoon; Rippey, Caroline; Taylor, Ethan

  Intelligent Transportation Systems (ITS) are gaining popularity among governments, businesses, and individuals due to their potential to make travel safer and more efficient. Machine learning for traffic prediction has emerged as a promising subfield of ITS, with the potential to aid in routing planning, congestion management, and urban development. Traffic infrastructure and mobile devices collect large amounts of heterogeneous data that can be used to predict traffic conditions, including real-time traffic data such as traffic camera images, speed measurements, and volume counts, as well as long-term static data such as speed limits, road conditions, and surrounding geography and infrastructure. Despite the availability of traffic data, many current machine learning models struggle to handle the wide variety of data types and to address both temporal aspects of real-time data and spatial aspects of long-term static data. To address this, we propose a new enrichment learning model that integrates dynamic data containing varying numbers of instances with static data to create an enriched fixed-length vector which can be used with other machine learning methods to improve performance and identify regions important for prediction. Results show that this novel enrichment learning model can improve the performance of traditional machine learning methods in the task of predicting future traffic speeds.
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  Ankle muscle strength affects muscle forces during double leg hopping

  Vargas, Brooklyn L.; Miller, Michael F.; Daley, Monica A.; McNitt-Gray, Jill; Silverman, Anne K.

  Falls are a primary cause of morbidity and mortality in older adults, with dynamic balance decline often being the precursor to a fall. Declining lower limb strength has been linked to dynamic balance decline. Therefore, this study will evaluate the effect of ankle muscle weakness on muscle control and coordination of double leg hopping, a task that requires precise dynamic balance control. A healthy adult performed ten continuous double leg hops. Motion capture and ground reaction forces were collected. A model was developed in Visual3D (C-Motion, Inc.), and inverse kinematics (IK) of three hops were computed. The GRFs along with the IK solutions were exported to OpenSim v 4.4 and applied to a scaled musculoskeletal model. A Residual Reduction Algorithm (RRA) improved dynamic consistency. Computed Muscle Control (CMC) then determined the needed muscle excitation patterns. A weakened model was developed with reduced maximum isometric force of the MG, LG, and SOL to represent aging. Peak dynamic force from MG and SOL decreased by 16% and 3% respectively in the weakened model, while the LG increased by 16%, compensating for MG force deficits. Several agonist muscles in the weakened model increased their peak force output, suggesting they are compensating for the weakened MG, LG, and SOL. The ankle reserve actuator peak torque increased by 135% in the weakened model. These findings indicate ankle muscle weakness associated with aging affects hopping strategy and muscle recruitment. Strength should be preserved to maintain movement and prevent dynamic balance decline.
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  Glaciers in the south: a comprehensive framework for evaluating public school district capacities for cryosphere education

  Miller, Ashleigh; Verboncoeur, Hannah; Reddy, Elizabeth; Siegfried, Matthew

  Rising sea levels have disproportionately large impacts on Southern coastal regions of the United States, and to a greater degree among communities therein affected by socioeconomic inequalities. Despite this, research in one of the leading causes of global sea level rise, melting ice (i.e., the cryosphere), is largely left behind in the curricula of public middle and high school institutions throughout these southern states. As rates of sea level rise continue to increase, an assessment of educational capacities within the context of present-day access to climate and cryosphere education in the United States becomes increasingly important. In this study, we apply an inductive coding method to current public-school curricula at the "8th to 12th" grade levels to assess the capacities of Southern schools to support strengthened cryosphere and sea level rise education. This developed framework can be applied to school systems across the United States and ranks availability of access, capacities form and connections to cryosphere and sea level rise education. The results of this study indicate a great potential to connect sea level rise and cryosphere education to the impacts and experiences of coastal communities in the United States, as well as capacities to forge new collaborations between funded university-level research centers and local communities to support educational access. Future work will quantify the identified capacities within southern public school science curricula in an actionable manner for use by Boards of Education, politicians, and scientists in sea level rise and cryospheric science spaces.
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  Development of OpenStudio model for CLT hotel

  Obluda, Caroline M.; Tabares-Velasco, Paulo Cesar

  Cross-laminated timber (CLT), a type of mass timber in which wood is secured in alternating directions, has emerged as an sustainable alternative to concrete or steel with a significantly lower carbon footprint. However, CLT properties depend on its moisture content and most building energy tools do not account for moisture transfer in building envelopes. This study develops a building energy modeling in OpenStudio for a hotel in Fort Jackson, North Carolina, that utilizes CLT to compare against field data. When the data is collected from the hotel, the OpenStudio model will be calibrated to the measurements so that future models can more accurately predict the properties of the building envelope in CLT buildings.
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  Mathematical modeling to investigate dual pathway inhibition by anticoagulant and antiplatelet drugs

  Tubbs, Azlan M.; Leiderman, Karin

  The purpose of blood coagulation is to halt blood flow from a damaged vessel for the vessel to heal and repair. Blood coagulation occurs as overlapping enzymatic events, which are strongly regulated by platelet surfaces. Coagulation begins when the wall of the blood vessel is injured and ends when aggregated platelets seal the injury. Dual pathway inhibition, in which both antiplatelet and anticoagulant drugs are used in combination, promises therapies for reducing risks of harmful clot development that may lead to coronary and cerebrovascular ischemia. Although information exists concerning the effectiveness and success of dual pathway inhibition therapies, the mechanism remains ambiguous due to a lack of ability to observe detailed biochemical interactions during the dynamic clotting process. Mathematical modeling allows for efficient simulations of the clotting process and provides access to the dynamic concentrations of all proteins, cells, and interactions within the system under the influence of flow. This project builds on a mechanistic mathematical model of flow-mediated coagulation and platelet deposition. A combination of the antiplatelet aspirin and the anticoagulant rivaroxaban is considered in the model, and the clotting process is simulated for various concentrations of drugs and injury types.
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  The social impacts of the Gold King mine spill: an interdisciplinary approach

  Knies, Declan, A.; Holmes, Rebecca; Kroepsch, Adrianne; Singha, Kamini

  On August 5th, 2015, 3 million gallons of mustard-yellow mine wastewater was unleashed onto Cement Creek, the Animas River, and eventually the mighty San Juan river. In the days, weeks, and months that followed, a glaring question presented itself. Who's to blame? The event brought up long-existing problems and questions about the state of water quality in the San Juan mountains. In this study, we focus on the perspective of 3 of the biggest agents: the town of Silverton, the city of Durango, and the Navajo Nation. Each of these actors have an independent newspaper which presents a valuable look into how the local community perceived this event. By analyzing keywords, impactful quotes, and unique phrasing, we were able to gauge the response to each community over time. According to a preliminary sample of the Durango Herald (Durango's local newspaper), the EPA was the primary group blamed for the spill with no one at fault being the next largest group. This can help us contextualize Durango and La Plata County when comparing this to other impacted areas and historical information. By analyzing the local newspapers in impacted areas, we are able to gain a better idea of both the local impact and perception of the event, leading to more objective, educated understanding of the catastrophe.
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  Nanoscale rock-salt structured high-entropy metal oxides for catalysis

  Kelly, Zek E.; Brim, Elliot; Richards, Ryan

  High-entropy materials are a new class of solids that are rapidly growing in scientific interest differ because they are formed and stabilized by the large configurational entropy generated by their multi-elemental composition. Due to the large range of possible multi-elemental configurations, it is possible to tune the chemical and physical properties for specific electronic and catalytic purposes. The focus of this research is the wet chemical synthesis and characterization of nanoscale high-entropy metal oxides with a rock-salt structure. Specifically, this research focuses on high-entropy oxide nanomaterial catalysts that are made from earth-abundant and inexpensive precursor metals. Although there have been recent reports regarding very interesting catalytic properties, the ability to control the structure of this class of materials on the nanoscale remains a challenge. If this class of materials can be tailored in terms of both composition and nanoscale morphology, they offer a path using earth abundant systems to replace current catalytic materials which are generally rare and expensive metals such as platinum, iridium, and rhodium.
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  Interaction of 2D particles and phospholipid monolayers

  Regidor, Kailyn I.; Chacon, Amy; Samaniuk, Joseph R.

  The goal of this project is to understand how 2D particles at fluid-fluid interfaces interact with phospholipid monolayers found in biology, such as the lung surfactant DPPC. In the project, the main objective was to fabricate mono layer graphene to a certain size and shape to study their interactions with microscopy.
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  Nanostructured titanium for medical devices

  Ferro, Kelsey R.; Campbell, Connor; Lowe, Terry C.

  The bulk and surface properties of pure titanium can be enhanced by nanostructuring to create a new generation of metals for medical implants. The healing response of bone to nanostructured titanium implants can be accelerated 20-fold by altering the metal's crystal size and grain boundary density. In addition, the strength of nanostructured titanium compared to conventional titanium can be increased between 30% to 100%. To incorporate these benefits into medical implants such as spinal rod or dental implants, nanostructuring must be applied to long rods or bars of titanium. One method of nanostructuring titanium is to subject long rods to high shear deformation. However, while this deformation creates nanoscale grains, it also imparts some residual stresses, which must be removed by annealing. In my research, we evaluated the annealing response of nanostructured titanium. Bars of pure titanium nanostructured by High Shear Deformation (HSD) were subjected to 1 hour annealing treatments between 200°C and 375°C. We evaluated the annealing response by measuring the microhardness. We confirmed the unusual phenomenon of "annealing hardening" that is unique to nanostructured metals. Generally, annealing reduces the hardness and strength of pure metals. But in the case of nanostructured titanium annealing can increase the strength. We were able to determine an optimum annealing temperature of 275°C.
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  Mathematical mechanics of one-dimensional filaments in three-dimensional space

  Hofer, Jacob S.; Strong, Scott A.

  A one-dimensional filament is a useful mathematical object for modeling a variety of physical phenomena such as vortex filaments. Through a description of the filament using the tangent, normal, and binormal vectors, we get a more meaningful description of the curve in terms of curvature and torsion. Hasimoto's transformation defines a mapping between a kinematic evolution of a space curve and nonlinear scalar equations evolving its intrinsic curve geometry. Through this transformation, the problem of understanding the time evolution of curves can be greatly simplified, yielding useful equations which arise in other areas of nonlinear physics. In our work, we generalize this transformation on arbitrary flows and test against several existing kinematic flows. We consider the time dynamics of length and bending energy to see that binormal flows are generally length-preserving, and bending energy is fragile and unlikely to be conserved in the general case. By describing a space curve in terms of curve geometry, we can perform a transformation that yields a useful description of the time evolution of the curve. Through a generalization of this transformation, we can better understand how the kinematic equation dictates the behavior of the curve, and how this relates to the modeling of physical phenomena.
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  Characterization of low-cost methane sensors for outdoor use

  Sullivan, Neal P.; Yang, Jayoon; Evans, Johnathan G.

  Methane is known as a major greenhouse gas and there are not many economical ways of measuring smaller methane concentrations. Currently, small concentration methane sensing technology is expensive and difficult to apply on a large scale. A lack of inexpensive methane-sensing technologies leaves many small leaks in various machines undetectable. BPX Energy (Denver, CO) partnered with the Colorado Fuel Cell Center at Colorado School of Mines to characterize inexpensive, linearly applicable methane sensors for greenhouse gas detection. In this effort, the team at the Colorado Fuel Cell Center has created a testing apparatus featuring an environmental chamber to quantify sensor response over a range of known methane concentrations, operating temperatures, and humidities. Gas composition is regulated using mass flow controllers. Chamber temperature and humidity are measured by an Arduino interfacing with additional data acquisition hardware. Sensor response is measured using National Instrument's PCI analog-to-digital tools. The control and data collection are fully controlled by a LabView script designed to execute scripted tests. The research includes extensive data collection, curve fitting and analysis. In addition to characterizing sensor response to changes in humidity and temperature, the large set of sensors examined provides insight to the consistency of sensor outputs, and precision between sensors.
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  Pairwise entanglement networks as a probe into non-equilibirum quantum dynamics

  Barton, Brandon A.; Carr, Lincoln D.; Diniz Behn, Cecilia; Gong, Zhexuan

  Following a sudden change of system parameters known as a quantum quench, the state of a quantum system can exhibit out-of-equilibrium dynamics. When the quench is across a critical point, a dynamical phase transition can occur, indicated by non-analytic behavior in a quantity known as Loschmidt echo. However, measuring the Loschmidt echo requires measurement of the entire quantum state, which is experimentally challenging, even for a moderate system size of a few tens of quantum particles. To address the challenge of detecting dynamical phase transitions, we investigate the possibility of using only information from two-body reduced states of a quantum many-body system for identifying dynamical phase transitions. These two-body reduced states allow us to calculate a network of different pairwise entanglement measures, including connected correlations, concurrence, and mutual information. As the measurement of all two-body reduced states only requires resources quadratic in system size, obtaining pairwise networks of these entanglement measures is experimentally practical. Upon attaining the pairwise networks, we directly examine the weighted adjacency matrices using network science and spectral graph analysis. Our results show that concurrence, an entanglement monotone, oscillates in phase with the rate function. As an example of our procedure, we consider a long-range transverse field Ising model with power-law interactions in the coupling strength. We further show that our methods may provide a considerably more efficient method for probing dynamical phase transitions in a large quantum many-body system. This work also paves the way for characterizing the role of pairwise entanglement in identifying critical phenomena.

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