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Integrated Optical Field Sampling Platform

In collaboration with MIT, Researchers at the University of California, Davis have contributed to the development of an Integrated Opitcal Sampling Platform.

Modified Fibonacci Switched Capacitor Converter with Reduced Switch Stress and Increased Efficiency

Researchers at the University of California, Davis have developed a technology that introduces an alternative topology for Fibonacci switched-capacitor converters that significantly reduces switch losses and improves efficiency.

Method and System for Signal Separation in Wearable Sensors with Limited Data (with Applications to Transabdominal Fetal Oximetry)

Researchers at the University of California, Davis have developed method for separating quasi-periodic mixed-signals using a single data trace, enhancing wearable sensor applications.

Electrolyte Formulations for Non-Aqueous Flow Batteries

Researchers at the University of California, Davis have developed a technology that introduces new electrolyte compositions that significantly enhance the stability and efficiency of non-aqueous flow batteries.

Spectral Kernel Machines With Electrically Tunable Photodetectors

       Spectral machine vision collects both the spectral and spatial dependence (x,y,λ) of incident light, containing potentially useful information such as chemical composition or micro/nanoscale structure.  However, analyzing the dense 3D hypercubes of information produced by hyperspectral and multispectral imaging causes a data bottleneck and demands tradeoffs in spatial/spectral information, frame rate, and power efficiency. Furthermore, real-time applications like precision agriculture, rescue operations, and battlefields have shifting, unpredictable environments that are challenging for spectroscopy. A spectral imaging detector that can analyze raw data and learn tasks in-situ, rather than sending data out for post-processing, would overcome challenges. No intelligent device that can automatically learn complex spectral recognition tasks has been realized.       UC Berkeley researchers have met this opportunity by developing a novel photodetector capable of learning to perform machine learning analysis and provide ultimate answers in the readout photocurrent. The photodetector automatically learns from example objects to identify new samples. Devices have been experimentally built in both visible and mid-infrared (MIR) bands to perform intelligent tasks from semiconductor wafer metrology to chemometrics. Further calculations indicate 1,000x lower power consumption and 100x higher speed than existing solutions when implemented for hyperspectral imaging analysis, defining a new intelligent photodetection paradigm with intriguing possibilities.

A High Flux Microchannel Solar Receiver for Converting Solar Energy into Heat

Researchers at the University of California, Davis have developed an innovative technology that incorporates advanced microchannel architecture into scalable solar thermal receiver unit cells, enabling highly efficient solar energy conversion.

Rollover Prediction and Alert for All-Terrain Vehicle

Researchers at the University of California Davis have developed a system designed to predict and prevent ATV rollovers, enhancing rider safety.

Technique for Safe and Trusted AI

Researchers at the University of California Davis have developed a technology that enables the provable editing of DNNs (deep neural networks) to meet specified safety criteria without altering their architecture.

Piezoelectric Transformers For Power Conversion

      The demand for miniaturized power electronics with increased efficiency and performance motivates the exploration of piezoelectric structures as alternative passive components; piezoelectric components store energy in mechanical compliance and inertia with extremely high quality factors and energy densities significantly greater than those of magnetics at small scales. Recent magnetic-less dc-dc converter designs based on single-port piezoelectric resonators (PRs) have demonstrated power stage efficiencies of 99% and PR power handling densities of up to 5.7 kW/cm3. While marking tremendous milestones, such performance has only been achieved in non-isolated dc-dc converters with mild (2:1) voltage conversion ratios, confining the utility of piezoelectric-based power conversion to a narrow subset of applications.       Piezoelectrics may be expanded to a broader set of applications through use of multi-port piezoelectric transformers (PTs), which offer the same advantages as PRs but with the added potential for galvanic isolation and inherent voltage transformation. The present invention overcomes standing performance shortcomings in isolated magnetic-less PT-based dc-dc converters, providing a framework for high-efficiency piezoelectric transformer (PT) designs (wherein isolated PTs serve as the primary passive components in isolated dc-dc converters). One of the proposed PT designs is validated in a dc-dc power converter prototype and demonstrates a peak efficiency of 97.5%. The measured performance represents a 17x reduction in loss ratio compared to previous isolated magnetic-less PT-based dc-dc converter designs, and expands the value of piezoelectrics to applications requiring isolation.

Photonic Physically Unclonable Function for True Random Number Generation and Biometric ID for Hardware Security Applications

Researchers at the University of California, Davis have developed a technology that introduces a novel approach to hardware security using photonic physically unclonable functions for true random number generation and biometric ID.

Photothermal Patterning Flow Cell

Researchers at the University of California, Davis have developed a photothermal patterning flow cell that enables precise and efficient patterning of polymer films, compatible with existing cleanroom photolithography equipment.

3D Photonic and Electronic Neuromorphic Artificial Intelligence

Researchers at the University of California, Davis have developed an artificial intelligence machine that uses a combination of electronic neuromorphic circuits and photonic neuromorphic circuits.

Haptic Smart Phone-Cover: A Real-Time Navigation System for Individuals with Visual Impairment

Researchers at the University of California, Davis have developed a haptic interface designed to aid visually impaired individuals in navigating their environment using their portable electronic devices.

Ultra-High Range Resolution Doppler Radar Front End With Quadrature-Less Coherent Demodulation

Researchers at the University of California, Davis have developed a Doppler radar front end to overcome detection nulls without quadrature demodulation.

Heated Dynamic Headspace Sampling Device for Volatile Organic Compounds (VOCs) from a Surface

Researchers at the University of California, Davis have developed a technology that offers a sophisticated solution for collecting and measuring gas emissions from surfaces, particularly skin, with high sensitivity and specificity.

Mechanical Power Generation Through Passive Radiative Cooling

Researchers at the University of California, Davis have developed an approach to generating mechanical power from the earth's ambient thermal radiation using a Stirling engine.

Frequency Programmable MRI Receive Coil

In magnetic resonance imaging (MRI) scanners, the detection of nuclear magnetic resonance (NMR) signals is achieved using radiofrequency, or RF, coils. RF coils are often equivalently called “resonance coils” due to their circuitry being engineered for resonance at a single frequency being received, for low-noise voltage gain and performance. However, such coils are therefore limited to a small bandwidth around the center frequency, restricting MRI systems from imaging more than one type of nucleus at a time (typically just hydrogen-1, or H1), at one magnetic field strength.To overcome the inherent restriction without sacrificing performance, UC Berkeley researchers have developed an MRI coil that can perform low-noise voltage gain at arbitrary relevant frequencies. These frequencies can be programmably chosen and can include magnetic resonance signals from any of various nuclei (e.g., 1H, 13C, 23Na, 31P, etc.), at any magnetic field strength (e.g., 50 mT, 1.5T, 3T, etc.). The multi-frequency resonance can be performed in a single system. The invention has further advantages in terms of resilience due to its decoupled response relative to other coils and system elements.

Simultaneous 225Ac & 18F Production with Standard Medical Cyclotrons

High flux (e.g., greater than 1012 n/s/cm2) neutrons with energies between 8 and 30 MeV are needed for a number of applications including radioisotope production. However, none of the existing neutron sources available can fulfill these requirements. Neutron flux intensities from typical neutron sources using Deuterium-Tritium (DT) fusion are typically more than 2 orders of magnitude lower in intensity than what is needed for making production practical. Deuterium-Deuterium (DD) fusion sources provide a spectrum which is too low in energy to perform the nuclear reactions needed for isotope production. High-energy proton accelerator-driven spallation sources produce isotopes with significant co-production of unwanted radioisotopes, due to a neutron spectrum which is far higher in energy than required. While accelerator-driven neutron sources using deuteron breakup have been shown to be a viable pathway for producing a range of isotopes including actinium-225 1, a limited number of machines capable of producing ~30 MeV deuteron beams exist commercially. To address this problem, researchers at UC Berkeley have developed systems and methods for producing radionuclides using accelerator-driven fast neutron sources, and more specifically for producing actinium-225, an inherently-safe, fast neutron source based on low energy proton accelerators used throughout the world to support positron emission tomography.

Compact Series Elastic Actuator Integration

      While robots have proven effective in enhancing the precision and time efficiency of MRI-guided interventions across various medical applications, safety remains a formidable challenge for robots operating within MRI environments. As the robots assume full control of medical procedures, the reliability of their operation becomes paramount. Precise control over robot forces is particularly crucial to ensure safe interaction within the MRI environment. Furthermore, the confined space in the MRI bore complicates the safe operation of human-robot interaction, presenting challenges to maneuverability. However, there exists a notable scarcity of force-controlled robot actuators specifically tailored for MRI applications.       To overcome these challenges, UC Berkeley researchers have developed a novel MRI-compatible rotary series elastic actuator module utilizing velocity-sourced ultrasonic motors for force-controlled robots operating within MRI scanners. Unlike previous MRI-compatible SEA designs, the module incorporates a transmission force sensing series elastic actuator structure, while remaining compact in size. The actuator is cylindrical in shape with a length shorter than its diameter and integrates seamlessly with a disk-shaped motor. A precision torque controller enhances the robustness of the invention’s torque control even in the presence of varying external impedance; the torque control performance has been experimentally validated in both 3 Tesla MRI and non-MRI environments, achieving a settling time of 0.1 seconds and a steady-state error within 2% of its maximum output torque. It exhibits consistent performance across low and high external impedance scenarios, compared to conventional controllers for velocity-sourced SEAs that struggle with steady-state performance under low external impedance conditions.

Compact Catadioptric Mapping Optical Sensor For Parallel Goniophotometry

      Goniophotometers measure the luminance distribution of light emitted or reflected from a point in space or a material sample. Increasingly there is a need for such measurements in real-time, and in real-world situations, for example, for daylight monitoring or harvesting in commercial and residential buildings, design and optimization of greenhouses, and testing laser and display components for AR/VR and autonomous vehicles, to name a few. However, current goniophotometers are ill-suited for real-time measurements; mechanical scanning goniophotometers have a large form factor and slow acquisition times. Parallel goniophotometers take faster measurements but suffer from complexity, expense, and limited angular view ranges (dioptric angular mapping systems) or strict form factor and sample positioning requirements (catadioptric angular mapping systems). Overall, current goniophotometers are therefore limited to in-lab environments.      To overcome these challenges, UC Berkeley researchers have invented an optical sensor  for parallel goniophotometry that is compact, cost-effective, and capable of real-time daylight monitoring. The novel optical design addresses key size and flexibility constraints of current state-of-the-art catadioptric angular mapping systems, while maximizing the view angle measurement at 90°. This camera-like, angular mapping device could be deployed at many points within a building to measure reflected light from fenestrations, in agricultural greenhouses or solar farms for real-time monitoring, and in any industry benefitting from real-time daylight data.

Low Heat Loss Latent Heat Battery (LHB)

Researchers at the University of California, Davis have developed a green technology designed for the efficient storage and discharge of heat energy sourced from intermittent green energy supplies.

Improved Optical Atomic Clock In The Telecom Wavelength Range

Optical atomic clocks have taken a giant leap in recent years, with several experiments reaching uncertainties at the 10−18 level. The development of synchronized clock networks and transportable clocks that operate in extreme and distant environments would allow clocks based on different atomic standards or placed in separate locations to be compared. Such networks would enable relativistic geodesy, tests of fundamental physics, dark matter searches, and more. However, the leading neutral-atom optical clocks operate on wavelengths of 698 nm (Sr) and 578 nm (Yb). Light at these wavelengths is strongly attenuated in optical fibers, posing a challenge to long-distance time transfer. Those wavelengths are also inconvenient for constructing the ultrastable lasers that are an essential component of optical clocks. To address this problem, UC Berkeley researchers have developed a new, laser-cooled neutral atom optical atomic clock that operates in the telecommunication wavelength band. The leveraged atomic transitions are narrow and exhibit much smaller black body radiation shifts than those in alkaline earth atoms, as well as small quadratic Zeeman shifts. Furthermore, the transition wavelengths are in the low-loss S, C, and L-bands of fiber-optic telecommunication standards, allowing the clocks to be integrated with robust laser technology and optical amplifiers. Additionally, the researchers have identified magic trapping wavelengths via extensive studies and have proposed approaches to overcome magnetic dipole-dipole interactions. Together, these features support the development of fiber-linked terrestrial clock networks over continental distances.

Electrified Filters For Hexavalent Chromium Removal

      While chromium (Cr) is recognized as an essential micronutrient, its hexavalent form, Cr(VI), is one of the ubiquitous metal contaminants prevalent in groundwater with toxicity and carcinogenic risks. After years of debate and analysis, California regulators adopted a limit of 10 ppb for Cr(VI) in drinking water in April 2024, which should lead to more stringent regulation of Cr(VI) nationwide and attract up to hundreds of millions of dollars in investment. Electroreduction of Cr(VI) to Cr(III) is a promising strategy for detoxication of Cr(VI), but the noble-metal-based and nanomaterial-based electrodes typically used for Cr(VI) reduction are expensive or require a complicated preparation process. Moreover, the majority of flat-sheet electrodes used in flow-by operation mode are constrained by surface area, which causes low mass transport, detoxication efficiency, and current efficiency, and generates high energy consumption.       To meet these challenges, UC Berkeley researchers have developed a stainless-steel filter with the capability of selectively reducing Cr(VI) to Cr(III) in-situ during a single pass filtration process. The filter doesn’t require chemical inputs or generate waste sludge. It has demonstrated minimal electric energy consumption while removing Cr(VI) from real groundwater samples (Coachella Valley Water District, California, calculated at 0.00076 $/m3 –beating other techniques by several orders of magnitude). The water flux of the filter is adjustable to meet specific, realistic water treatment requirements, and it can furthermore be regenerated in-situ for long-term performance without off-site chemical-dependent cleaning procedures. This environmentally friendly filter efficiently removes Cr(VI) from traditional and non-traditional water sources using minimal energy input and with zero discharge, addressing critical issues in water scarcity and Cr(VI) contamination.

Silicon Solar Cells that Absorb Solar Photons Above 2.2 eV and are Transparent to Solar Photons Below 2.2 eV

Traditionally, land can be used for either crop growth or energy production. This technology optimizes the efficiency of land use by combining both. Researchers at the University of California, Davis have developed solar cell designs that absorb only specific solar photons (> 2.2 eV) to create electricity, while letting through beneficial light (< 2.2 eV) for efficient crop growth.

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