Phys.org January 4, 2021 Due to material imperfections, some amount of light is reflected backwards in microresonators which disturbs their function. To reduce the unwanted backscattering an international team of researchers (UK, Germany) used the principle of noise cancelling headphone and introduced out-of-phase light to cancel out optical interference. To generate the out-of-phase light, the researchers position a sharp metal tip close to the microresonator surface. The tip also causes light to scatter backwards. As the phase of the reflected light can be chosen by controlling the position of the tip, backscattered light’s phase can be set so it annihilates […]
Category Archives: Sensors
Wireless, ultra-thin and battery-free strain sensors that are 10 times more sensitive
EurekAlert December 15, 2020 Performance of conventional strain sensors has always been limited by the nature of sensing materials used, and users have limited options of customizing the sensors for specific applications. Researchers in Singapore have developed flexible, stretchable, and electrically conductive nanomaterials called MXenes and fabricated strain sensors which are ultra-thin, battery-free and transmit data wirelessly. The sensors are 10 times more sensitive when measuring minute movements of industrial robotic arms, compared to existing technology. In precision manufacturing it helps improve the overall safety of robotic arms by providing automated feedback on precise movements with an error margin below […]
Breakthrough optical sensor mimics human eye, a key step toward better AI
Science Daily December 8, 2020 Neuromorphic processors are still designed for traditional computer architectures. Researchers at the State University of Oregon have shown that a simple photosensitive capacitor will inherently reproduce certain aspects of biological retinas. They found that capacitors based on metal halide perovskites will output a brief voltage spike in response to changes in incident light intensity but output zero voltage under constant illumination. The new sensor could be a perfect match for the neuromorphic computers that will power the next generation of artificial intelligence in applications like self-driving cars, robotics, and advanced image recognition…read more. Open Access […]
Smellicopter: An obstacle-avoiding drone that uses a live moth antenna to seek out smells
Science Daily December 8, 2020 A team of researchers in the US (University of Washington, University Maryland) used antennae from the Manduca sexta hawkmoth for Smellicopter. One scent molecule in a moth antenna can trigger lots of cellular responses amplifying chemical signals. This process is super-efficient, specific, and fast. Researchers placed moths in the fridge to anesthetize them before removing an antenna. Once separated from the live moth, the antenna stays biologically and chemically active for up to four hours which can be extended by storing antennae in the fridge. In tests the moth antenna reacted more quickly and took […]
Quantum nanodiamonds may help detect disease earlier
Science Daily November 25, 2020 Researchers in the UK investigated fluorescent nanodiamonds as an ultrasensitive label for in vitro diagnostics, using a microwave field to modulate emission intensity and frequency-domain analysis to separate the signal from background autofluorescence, which typically limits sensitivity. Focusing on the widely used, low-cost lateral flow format as an exemplar, they achieved a detection limit of 8.2 × 10−19 molar for a biotin–avidin model, 105 times more sensitive than that obtained using gold nanoparticles. Single-copy detection of HIV-1 RNA can be achieved with the addition of a 10-minute isothermal amplification step. This ultrasensitive quantum diagnostics platform […]
Analysis paves way for more sensitive quantum sensors
Nanowerk November 16, 2020 Researchers at the University of Chicago proposed creating a string of photonic cavities, where photons can be transported to adjacent cavities. Such a string could be used as a quantum sensor. By harnessing non-Hermitian dynamics, where dissipation leads to interesting consequences, they were able to calculate that a string of these cavities would increase the sensitivity of the sensor much more than the number of cavities added. In fact, it would increase the sensitivity exponentially in system size. To prove the theory, they are building a network of superconducting circuits that can move photons between cavities. […]
DARPA’s plan for an airborne COVID detector
Defense Systems November 11, 2020 The small and variable characteristics of the virus combined with complex indoor environments make using a single detection and measurement technique extraordinarily difficult. Optical environmental sensors, which can offer fast detection times, are not always able to discriminate between benign and pathogenic material. The SenSARS program (Pre-solicitation) aims to overcome these existing challenges to environmental monitoring. DARPA is primarily interested in three use cases: detecting the virus in a 50-cubic-meter office, similar detection in a 300-cubic-meter conference room or classroom, and central monitoring of HVAC systems in buildings up to 10 stories. Solutions must have […]
Laying the groundwork for ultra-thin, energy efficient photodetector on Gorilla glass
Nanowerk November 2, 2020 Direct growth of high-performance, scalable, and reliable electronic materials on glass is difficult owing to low thermal budget. Researchers at the Pennsylvania State University have addressed the issue by relatively low-temperature (<600 °C) metal–organic chemical vapor deposition growth of atomically thin MoS2 on multicomponent glass and fabrication of low-power phototransistors using atomic layer deposition (ALD)-grown, high-k, and ultra-thin Al2O3 as the top-gate dielectric, circumventing the challenges associated with the ALD nucleation of oxides on inert basal planes of van der Waals materials. The MoS2 photodetectors demonstrate the ability to detect low-intensity visible light at high speed […]
Researchers invent flexible and highly reliable sensor
Science Daily November 2, 2020 Real-time health monitoring and sensing abilities of robots require soft electronics. Unlike rigid devices, being elastic and pliable makes their performance less repeatable due to hysteresis. Researchers in Singapore have developed a sensor, Tactile Resistive Annularly Cracked E-Skin (TRACE) which addresses the trade-off between sensitivity and hysteresis in tactile sensors when using soft materials. They discovered that piezoresistive sensors made using an array of three-dimensional metallic annular cracks on polymeric microstructures possess high sensitivities, low hysteresis over a wide pressure range and have fast response. They have demonstrated that TRACE sensors can accurately detect and […]
AI detects hidden earthquakes
Science Daily October 22, 2020 Earthquake signal detection and seismic phase picking are challenging tasks in the processing of noisy data and the monitoring of microearthquakes. A team of researchers (Stanford University, Georgia Institute of Technology) has developed a global deep-learning model for simultaneous earthquake detection and phase picking. Performing these two related tasks in tandem improves model performance in each individual task by combining information in phases and in the full waveform of earthquake signals by using a hierarchical attention mechanism. They applied their model to 5 weeks of continuous data recorded during 2000 Tottori earthquakes in Japan and […]