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Demonstration of Acoustically Driven Ferromagnetic Resonance Using Leaky Surface Acoustic Waves in Lithium Tantalate

IEEE International Symposium on Applications of Ferroelectrics, ISAF 2023, International Symposium on Integrated Functionalities, ISIF 2023 and Piezoresponse Force Microscopy Workshop, PFM 2023, Proceedings

Tiwari, Sidhant; Jarzembski, Amun; Siddiqui, Aleem; Reyna, Robert; Paldi, Robynne L.; Branch, Darren W.

Radio frequency (RF) magnetic devices are key components in RF front ends. However, they are difficult to miniaturize and remain the bulkiest components in RF systems. Acoustically driven ferromagnetic resonance (ADFMR) offers a route towards the miniaturization of RF magnetic devices. The ADFMR literature thus far has focused predominantly on the dynamics of the coupling process, with relatively little work done on the device optimization. In this work, we present an optimized 2 GHz ADFMR device utilizing relaxed SPUDT transducers in lithium tantalate. We report an insertion loss of -13.7 dB and an ADFMR attenuation constant of -71.7 dB/mm, making this device one of the best performing ADFMR devices to date.

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Finite Element Simulation of the Acoustic Pressure Inside a Beverage Container for Non-Thermal, Ultrasound-based Pasteurization

Branch, Darren W.

The purpose of this effort is to investigate whether large acoustic pressure waves can be transmitted inside beverage containers to enable pasteurization. Acoustic waves are known to induce large nonlinear compressive forces and shock waves in fluids, suggesting that compression waves may be capable of damaging bacteria inside beverage containers without appreciably increasingly the temperature or altering the freshness and flavor of the beverage contents. Although a combined process such as thermosonication (e.g., sonication with heating) is likely more efficient, it is instructive to compute the acoustic pressure field distribution inside the beverage container. The COMSOL simulations used two and three-dimensional models of beverage containers placed in a water bath to compute the acoustic pressure field. A limitation of these COMSOL models is that they cannot determine the bacterial lysis efficiency, rather the models provide an indirect metric of bacterial lysis based on the magnitude of the pressure field and its distribution.

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Nanocomposite-Seeded Epitaxial Growth of Single-Domain Lithium Niobate Thin Films for Surface Acoustic Wave Devices

Advanced Photonics Research

Paldi, Robynne L.; Qi, Zhimin; Misra, Shikhar; Lu, Juanjuan; Sun, Xing; Phuah, Xin L.; Branch, Darren W.; Siddiqui, Aleem; Wang, Haiyan

Epitaxial lithium niobate (LNO) thin films are an attractive material for devices across a broad range of fields, including optics, acoustics, and electronics. These applications demand high-quality thin films without in-plane growth domains to reduce the optical/acoustical losses and optimize efficiency. Twin-free single-domain-like growth has been achieved previously, but it requires specific growth conditions that might be hard to replicate. In this work, a versatile nanocomposite-seeded approach is demonstrated as an effective approach to grow single-domain epitaxial lithium niobate thin films. Films are grown through a pulsed laser deposition method and growth conditions are optimized to achieve high-quality epitaxial film. A comprehensive microstructure characterization is performed and optical properties are measured. A piezoelectric acoustic resonator device is developed to demonstrate the future potential of the nanocomposite-seeded approach for high-quality LNO growth for radio frequency (RF) applications.

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Handheld Biosensor for COVID-19 Screening

Branch, Darren W.; Hayes, Dulce C.

We have made significant progress toward the development of an integrated nucleic acid amplification system for Autonomous Medical Devices Incorporated (AMDIs) Optikus handheld diagnostic device. In this effort, we developed a set of loop-mediated isothermal amplification (LAMP) primers for SARS-CoV-2 and then demonstrate amplification directly on a surface acoustic wave (SAW) sensor. We built associated hardware and developed a C-code to control the amplification process. The goal of this project was to develop a nucleic amplification assay that is compatible with SAW sensors to enable both nucleic and serological testing in a single handheld diagnostic device. Toward this goal, AMDI is collaborating Sandia National Laboratories to develop a rapid, portable diagnostic screening device that utilizes Sandias unique surface acoustic wave biosensor (SAW) for COVID-19 detection. Previously, the SANDIA- AMDI SAW sensor has successfully detected multiple high-profile bacteria viruses, including Ebola, HIV, Sin Nombre, and Anthrax. Over the last two years, AMDI and SANDIA have significantly improved the sensitivity and detection capability of the SAW biosensor and have also developed a modular hand-held, portable platform called the Optikus, which uses CD microfluidics and handheld instrumentation to automate all sample preparation, reagent introduction, sample delivery, and measurement for a number of different assay targets. We propose to use this platform for the development of a rapid (%3C30 minutes), point-of-care diagnostic test for detection of COVID-19 from nasal swab samples.

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True Series Resonance Oscillator using Active Shunt Capacitance Cancellation

IFCS-ISAF 2020 - Joint Conference of the IEEE International Frequency Control Symposium and IEEE International Symposium on Applications of Ferroelectrics, Proceedings

Branch, Darren W.; Wessendorf, Kurt O.

A true series resonance oscillator has been developed for use with a wide-range of 1-port resonance-based sensors and devices. The oscillator effectively removes the shunt capacitance Co, allowing the true series resonance to be monitored, providing the optimum sensitivity across a wide range of frequencies (i.e. kilohertz to gigahertz), shunt capacitances, and quality factors (Q) for the first time. It is well-known that non-zero shunt capacitance alters the impedance by shifting the location of the impedance minimum and the zero-phase crossing while causing significant impedance distortion. We have developed an active shunt capacitance cancelling oscillator (ASSCO) that removes any shunt capacitance across the resonator by supplying the circuit an equal 'dummy' capacitance using a cancelling current. The oscillator does not require automatic gain control (AGC) and the resonator can be grounded to reduce parasitic contributions.

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COVID-19 LDRD Project Summaries

Treece, Amy; Corbin, William; Caskey, Susan; Krishnakumar, Raga; Williams, Kelly P.; Branch, Darren W.; Harmon, Brooke N.; Polsky, Ronen; Bauer, Travis L.; Finley, Patrick D.; Jeffers, Robert; Safta, Cosmin; Makvandi, Monear; Laird, Carl; Domino, Stefan P.; Ho, Clifford K.; Grillet, Anne M.; Pacheco, Jose L.; Nemer, Martin; Rossman, Grant A.; Koplow, Jeffrey; Celina, Mathew C.; Jones, Brad H.; Burton, Patrick D.; Haggerty, Ryan P.; Jacobs-Gedrim, Robin B.; Thelen, Paul M.

Sandia National Laboratories currently has 27 COVID-related Laboratory Directed Research & Development (LDRD) projects focused on helping the nation during the pandemic. These LDRD projects cross many disciplines including bioscience, computing & information sciences, engineering science, materials science, nanodevices & microsystems, and radiation effects & high energy density science.

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Investigation of a Solid-State Tuning Behavior in Lithium Niobate

2018 IEEE MTT-S International Microwave Workshop Series on Advanced Materials and Processes for RF and THz Applications, IMWS-AMP 2018

Branch, Darren W.; Nordquist, Christopher D.; Jensen, Daniel S.; Eichenfield, Matt; Douglas, James K.; Siddiqui, Aleem; Friedmann, Thomas A.

Electric field-based frequency tuning of acoustic resonators at the material level provides an enabling technology for building complex tunable filters. Tunable acoustic resonators were fabricated in thin plates (h/λ ∼ 0.05) of X-cut lithium niobate (90°, 90°, ψ = 170°). Lithium niobate is known for its large electromechanical coupling (SH: K2 40%) and thus applicability for low-insertion loss and wideband filter applications. We demonstrate the effect of a DC bias to shift the resonant frequency by 0.4% by directly tuning the resonator material. The mechanism is based on the nonlinearities that exist in the piezoelectric properties of lithium niobate. Devices centered at 332 MHz achieved frequency tuning of 12 kHz/V through application of a DC bias.

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Rapid nucleic acid extraction and purification using a miniature ultrasonic technique

Micromachines

Branch, Darren W.; Mcclain, Jaime; Murton, Jaclyn K.; James, Conrad D.; Achyuthan, Komandoor; Vreeland, Erika C.

Miniature ultrasonic lysis for biological sample preparation is a promising technique for efficient and rapid extraction of nucleic acids and proteins from a wide variety of biological sources. Acoustic methods achieve rapid, unbiased, and efficacious disruption of cellular membranes while avoiding the use of harsh chemicals and enzymes, which interfere with detection assays. In this work, a miniature acoustic nucleic acid extraction system is presented. Using a miniature bulk acoustic wave (BAW) transducer array based on 36° Y-cut lithium niobate, acoustic waves were coupled into disposable laminate-based microfluidic cartridges. To verify the lysing effectiveness, the amount of liberated ATP and the cell viability were measured and compared to untreated samples. The relationship between input power, energy dose, flow-rate, and lysing efficiency were determined. DNA was purified on-chip using three approaches implemented in the cartridges: a silica-based sol-gel silica-bead filled microchannel, nucleic acid binding magnetic beads, and Nafion-coated electrodes. Using E. coli, the lysing dose defined as ATP released per joule was 2.2× greater, releasing 6.1× more ATP for the miniature BAW array compared to a bench-top acoustic lysis system. An electric field-based nucleic acid purification approach using Nafion films yielded an extraction efficiency of 69.2% in 10 min for 50 μL samples.

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MEMS switching of contour-mode aluminum nitride resonators for switchable and reconfigurable radio frequency filters

Journal of Micromechanics and Microengineering

Nordquist, Christopher D.; Branch, Darren W.; Pluym, Tammy; Choi, Sukwon; Nguyen, Janet H.; Grine, Alejandro J.; Dyck, Christopher; Scott, Sean M.; Sing, Molly N.; Olsson, Roy H.

Switching of transducer coupling in aluminum nitride contour-mode resonators provides an enabling technology for future tunable and reconfigurable filters for multi-function RF systems. By using microelectromechanical capacitive switches to realize the transducer electrode fingers, coupling between the metal electrode finger and the piezoelectric material is modulated to change the response of the device. On/off switched width extensional resonators with an area of <0.2 mm2 demonstrate a Q of 2000, K 2 of 0.72, and >24 dB switching ratio at a resonator center frequency of 635 MHz. Other device examples include a 63 MHz resonator with switchable impedance and a 470 MHz resonator with 127 kHz of fine center frequency tuning accomplished by mass loading of the resonator with the MEMS switches.

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Comparative study of 0° X-cut and Y+36°-cut lithium niobate high-voltage sensing

Review of Scientific Instruments

Patel, Nishant; Branch, Darren W.; Schamiloglu, E.; Cular, S.

A comparison study between Y+36° and 0° X-cut lithium niobate (LiNbO3) was performed to evaluate the influence of crystal cut on the acoustic propagation to realize a piezoelectric high-voltage sensor. The acoustic time-of-flight for each crystal cut was measured when applying direct current (DC), alternating current (AC), and pulsed voltages. Results show that the voltage-induced shift in the acoustic wave propagation time scaled quadratically with voltage for DC and AC voltages applied to X-cut crystals. For the Y+36° crystal, the voltage-induced shift scales linearly with DC voltages and quadratically with AC voltages. When applying 5 μs voltage pulses to both crystals, the voltage-induced shift scaled linearly with voltage. For the Y+36° cut, the voltage-induced shift from applying DC voltages ranged from 10 to 54 ps and 35 to 778 ps for AC voltages at 640 V over the frequency range of 100 Hz–100 kHz. Using the same conditions as the Y+36° cut, the 0° X-cut crystal sensed a shift of 10–273 ps for DC voltages and 189–813 ps for AC voltage application. For 5 μs voltage pulses, the 0° X-cut crystal sensed a voltage induced shift of 0.250–2 ns and the Y+36°-cut crystal sensed a time shift of 0.115–1.6 ns. This suggests a frequency sensitive response to voltage where the influence of the crystal cut was not a significant contributor under DC, AC, or pulsed voltage conditions. The measured DC data were compared to a 1-D impedance matrix model where the predicted incremental length changed as a function of voltage. Furthermore, when the voltage source error was eliminated through physical modeling from the uncertainty budget, the combined uncertainty of the sensor (within a 95% confidence interval) decreased to 0.0033% using a Y + 36°-cut crystal and 0.0032% using an X-cut crystal for all the voltage conditions used in this experiment.

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Comparative study of 0° X-cut and y + 36°-cut lithium niobate high-voltage sensing

Review of Scientific Instruments

Patel, Nishant; Branch, Darren W.; Schamiloglu, E.

A comparison study between Y + 36°and 0°X-cut lithium niobate (LiNbO3) was performed to evaluate the influence of crystal cut on the acoustic propagation to realize a piezoelectric high-voltage sensor. The acoustic time-of-flight for each crystal cut was measured when applying direct current (DC), alternating current (AC), and pulsed voltages. Results show that the voltage-induced shift in the acoustic wave propagation time scaled quadratically with voltage for DC and AC voltages applied to X-cut crystals. For the Y + 36°crystal, the voltage-induced shift scales linearly with DC voltages and quadratically with AC voltages. When applying 5 μs voltage pulses to both crystals, the voltage-induced shift scaled linearly with voltage. For the Y + 36°cut, the voltage-induced shift from applying DC voltages ranged from 10 to 54 ps and 35 to 778 ps for AC voltages at 640 V over the frequency range of 100 Hz-100 kHz. Using the same conditions as the Y + 36°cut, the 0°X-cut crystal sensed a shift of 10-273 ps for DC voltages and 189-813 ps for AC voltage application. For 5 μs voltage pulses, the 0°X-cut crystal sensed a voltage induced shift of 0.250-2 ns and the Y + 36°-cut crystal sensed a time shift of 0.115-1.6 ns. This suggests a frequency sensitive response to voltage where the influence of the crystal cut was not a significant contributor under DC, AC, or pulsed voltage conditions. The measured DC data were compared to a 1-D impedance matrix model where the predicted incremental length changed as a function of voltage. When the voltage source error was eliminated through physical modeling from the uncertainty budget, the combined uncertainty of the sensor (within a 95% confidence interval) decreased to 0.0033% using a Y + 36°-cut crystal and 0.0032% using an X-cut crystal for all the voltage conditions used in this experiment.

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Nucleic acid extraction using a rapid, chemical free, ultrasonic technique for point-of-care diagnostics

IEEE International Ultrasonics Symposium, IUS

Branch, Darren W.; Smith, Gennifer T.; Vreeland, Erika C.; Blakemore, Robert; Alland, David

We have developed a miniature ultrasonic lysing system for the rapid release and extraction of Mycobacterium Tuberculosis (MTB) DNA. The prototype consists of two key sections, a disposable plastic manifold that hold sputum slides and a plastic cartridge with five fluidic DNA extraction channels. The MTB vaccine Bacillus Calmette-Guérin (BCG) was used as a simulant for MTB for all the lysing studies. The slide manifold houses up to five individual sputum slides and is processed by a computer to fill and load the cartridges with sputum suspensions from each slide. The plastic cartridge was developed to facilitate acoustic coupling through the bottom interface such that MTB/BCG can be lysed remotely. The disposable cartridge eliminated cross contamination problems and additional cleaning time. Due to the high power density, only 66 mW was required to lyse microliter BCG samples at the same level as the positive control (i.e. boiling for 30 minutes at 95 °C).

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Genomics-enabled sensor platform for rapid detection of viruses related to disease outbreak

Brozik, Susan M.; Polsky, Ronen; Campbell, Deanna M.; Manginell, Ronald; Moorman, Matthew W.; Edwards, Thayne L.; Anderson, John M.; Pfeifer, Kent B.; Branch, Darren W.; Wheeler, David R.

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Experimental validation of a high voltage pulse measurement method

Cular, S.; Patel, Nishant; Branch, Darren W.

This report describes X-cut lithium niobates (LiNbO3) utilization for voltage sensing by monitoring the acoustic wave propagation changes through LiNbO3 resulting from applied voltage. Direct current (DC), alternating current (AC) and pulsed voltage signals were applied to the crystal. Voltage induced shift in acoustic wave propagation time scaled quadratically for DC and AC voltages and linearly for pulsed voltages. The measured values ranged from 10 - 273 ps and 189 ps 2 ns for DC and non-DC voltages, respectively. Data suggests LiNbO3 has a frequency sensitive response to voltage. If voltage source error is eliminated through physical modeling from the uncertainty budget, the sensors U95 estimated combined uncertainty could decrease to ~0.025% for DC, AC, and pulsed voltage measurements.

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Origins and mitigation of spurious modes in aluminum nitride microresonators

Olsson, Roy H.; Wojciechowski, Kenneth E.; Branch, Darren W.

Recently reported narrow bandwidth, <;2%, aluminum nitride microresonator filters in the 100-500 MHz range offer lower insertion loss, 100x smaller size, and elimination of large external matching networks, when compared to similar surface acoustic wave filters. While the initial results are promising, many microresonators exhibit spurious responses both close and far from the pass band which degrade the out of band rejection and prevent the synthesis of useful filters. This paper identifies the origins of several unwanted modes in overtone width extensional aluminum nitride microresonators and presents techniques for mitigating the spurious responses.

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Toward exascale computing through neuromorphic approaches

Forsythe, James C.; Branch, Darren W.; Mckenzie, Amber T.

While individual neurons function at relatively low firing rates, naturally-occurring nervous systems not only surpass manmade systems in computing power, but accomplish this feat using relatively little energy. It is asserted that the next major breakthrough in computing power will be achieved through application of neuromorphic approaches that mimic the mechanisms by which neural systems integrate and store massive quantities of data for real-time decision making. The proposed LDRD provides a conceptual foundation for SNL to make unique advances toward exascale computing. First, a team consisting of experts from the HPC, MESA, cognitive and biological sciences and nanotechnology domains will be coordinated to conduct an exercise with the outcome being a concept for applying neuromorphic computing to achieve exascale computing. It is anticipated that this concept will involve innovative extension and integration of SNL capabilities in MicroFab, material sciences, high-performance computing, and modeling and simulation of neural processes/systems.

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Evaluation of arsenazo III as a contrast agent for photoacoustic detection of micromolar calcium transients

Progress in Biomedical Optics and Imaging - Proceedings of SPIE

Cooley, Erika J.; Kruizinga, Pieter; Branch, Darren W.; Emelianov, Stanislav

Elucidating the role of calcium fluctuations at the cellular level is essential to gain insight into more complex signaling and metabolic activity within tissues. Recent developments in optical monitoring of calcium transients suggest that cells integrate and transmit information through large networks. Thus, monitoring calcium transients in these populations is important for identifying normal and pathological states of a variety of systems. Though optical techniques can be used to image calcium fluxes using fluorescent probes, depth penetration limits the information that can be acquired from tissues in vivo. Alternatively, the calcium-sensitive dye arsenazo III is useful for optical techniques that rely on absorption of light rather than fluorescence for image contrast. We report on the use of arsenazo III for detection of calcium using photoacoustics, a deeply penetrating imaging technique in which an ultrasound signal is generated following localized absorption of light. The absorbance properties of the dye in the presence of calcium were measured directly using UV-Vis spectrophotometry. For photoacoustic studies, a phantom was constructed to monitor the change in absorbance of 25 μM arsenazo III at 680 nm in the presence of calcium. Subsequent results demonstrated a linear increase in photoacoustic signal as calcium in the range of 1 - 20 μM complexed with the dye, followed by saturation of the signal as increasing amounts of calcium were added. For delivery of the dye to tissue preparations, a liposomal carrier was fabricated and characterized. This work demonstrates the feasibility of using arsenazo III for photoacoustic monitoring of calcium transients in vivo. © 2010 Copyright SPIE - The International Society for Optical Engineering.

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Characterization and modeling of a bulk acoustic wave particle focusing device

2008 IEEE International Frequency Control Symposium, FCS

Ravula, Surendra K.; Branch, Darren W.; Westlake, Karl; Brener, Igal

In this paper, we discuss our work in the modeling and characterization of an acousdc-microfluidlc focusing device that uses standing bulk acoustic waves to focus particles under flow. Modeling was done using Comsol Multiphysics® (Comsol, Los Angeles, CA), a multiphysics FEM tool, and the performance of the device was assessed through coefficient of variance (CV) measurements using a confocal microscope. © 2008 IEEE.

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Shear horizontal surface acoustic wave microsensor for Class A viral and bacterial detection

Branch, Darren W.; Edwards, Thayne L.; Huber, Dale L.; Brozik, Susan M.

The rapid autonomous detection of pathogenic microorganisms and bioagents by field deployable platforms is critical to human health and safety. To achieve a high level of sensitivity for fluidic detection applications, we have developed a 330 MHz Love wave acoustic biosensor on 36{sup o} YX Lithium Tantalate (LTO). Each die has four delay-line detection channels, permitting simultaneous measurement of multiple analytes or for parallel detection of single analyte containing samples. Crucial to our biosensor was the development of a transducer that excites the shear horizontal (SH) mode, through optimization of the transducer, minimizing propagation losses and reducing undesirable modes. Detection was achieved by comparing the reference phase of an input signal to the phase shift from the biosensor using an integrated electronic multi-readout system connected to a laptop computer or PDA. The Love wave acoustic arrays were centered at 330 MHz, shifting to 325-328 MHz after application of the silicon dioxide waveguides. The insertion loss was -6 dB with an out-of-band rejection of 35 dB. The amplitude and phase ripple were 2.5 dB p-p and 2-3{sup o} p-p, respectively. Time-domain gating confirmed propagation of the SH mode while showing suppression of the triple transit. Antigen capture and mass detection experiments demonstrate a sensitivity of 7.19 {+-} 0.74{sup o} mm{sup 2}/ng with a detection limit of 6.7 {+-} 0.40 pg/mm{sup 2} for each channel.

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Hybrid method for the precise calculation of the general dyadic Greens functions for SAW and leaky wave substrates

Branch, Darren W.

Recently, the generalized method for calculation of the 16-element Green's function for analysis of surface acoustic waves has proven crucial to develop more sophisticated transducers. The generalized Green's function provides a precise relationship between the acoustic stresses and electric displacement on the three mechanical displacements and electric potential. This generalized method is able to account for mass loading effects which is absent in the effective permittivity approach. However, the calculation is numerically intensive and may lead to numerical instabilities when solving for both the eigenvalues and eigenvectors simultaneously. In this work, the general eigenvalue problem was modified to eliminate the numerical instabilities in the solving procedure. An algorithm is also presented to select the proper eigenvalues rapidly to facilitate analysis for all types of acoustic propagation. The 4 x 4 Green's functions and effective permittivities were calculated for materials supporting Rayleigh, leaky, and leaky longitudinal waves as demonstration of the method.

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Microfluidics and microacoustics for miniature flow cytometry

2007 NSTI Nanotechnology Conference and Trade Show - NSTI Nanotech 2007, Technical Proceedings

Ravula, Surendra K.; Branch, Darren W.; Sigman, Jennifer; Clem, Paul; Kaduchak, Gregory; Brener, Igal

Flow cytometry is an indispensable tool in clinical diagnostics, for example in cancer, AIDS, infectious disease outbreaks, microbiology, and others. The cost and size of existing cytometers precludes their entry into field clinics, water monitoring, agriculture/veterinary diagnostics, and rapidly deployable biothreat detection. Much of the cost and footprint of conventional cytometers is dictated by the high speed achieved by cells or beads in a hydrodynamically focused stream. This constraint is removed by using ultrasonic focusing in a parallel microfluidic architecture. In this paper, we describe our progress towards a microfabricated flow cytometer that uses bulk and microfabricated planar piezoelectric transducers in glass microfluidic channels. In addition to experimental data, initial modeling data to predict the performance of our transducers are discussed.

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Results 1–50 of 55
Results 1–50 of 55