Phys.org December 15, 2023 An international team of researchers (Belgium, Greece, Czech Republic) showed described in detail the process to obtain a fully packaged miniature photonic temperature sensor starting from bare PIC dies having Bragg grating sensors in a silicon waveguide. The PIC was interfaced from the back side using a 300 μm ball lens ensuring that the top surface remained clear of any interfacing fibers. Based on this they developed a solution for integrating a 1 mm × 1 mm sensor PIC with a single-mode fiber and packaging it in a 1.5 mm inner-diameter metal protective tube. A packaged […]
Resource-efficient and climate-friendly with sodium-ion batteries
Science Daily December 15, 2023 An international team of researchers (Sweden, Norway) performed a prospective life cycle assessment (LCA) of large-scale production of two different sodium-ion battery (SIB) cells with a cradle-to-gate system boundary. The SIB cells modeled have Prussian white cathodes and hard carbon anodes based only on abundant elements and thus constituted potentially preferable options to current lithium-ion battery (LIB) cells from a mineral resource. The functional unit was 1 kWh theoretical electricity storage capacity, and the specific energy density of the cells was 160 Wh/kg. For SIB cell materials, prospective inventory data was obtained from a generic […]
Something Strange Happens to The Human Brain During Zoom Calls
Science Alert November 3, 2023 It has long been understood that the ventral visual stream of the human brain processes features of simulated human faces. Recently, specificity for real and interactive faces has been reported in lateral and dorsal visual streams, raising new questions regarding neural coding of interactive faces and lateral and dorsal face-processing mechanisms. Researchers at Yale University compared neural activity during two live interactive face-to-face conditions where facial features and tasks remained constant while the social contexts (in-person or on-line conditions) were varied. Current models of face processing do not predict differences in these two conditions as […]
Ultrafast lasers map electrons ‘going ballistic’ in graphene with implications for next-gen electronic devices
Phys.org December 15, 2023 Researchers at the University of Kansas formed heterostructure by sandwiching a MoS2 and MoSe2 heterobilayer between two graphene monolayers. Transient absorption measurements revealed that the electrons and holes separated by the type-II interface between MoS2 and MoSe2 could transfer to the two graphene layers, respectively. With high spatial and temporal resolution, they found that while the holes in one graphene layer undergoes a classical diffusion process with a large diffusion coefficient of 65 cm2 s–1 and a charge mobility of 5000 cm2 V–1 s–1, the electrons in the other graphene layer exhibits a quasi-ballistic transport feature. […]
Top 10 Science and Technology Inventions for the Week of November 10, 2023
01. Bartering light for light: Scientists discover new system to control the chaotic behavior of light 02. Communing with nothingness 03. Efficient biohybrid batteries 04. Detecting hidden defects in materials using a single-pixel terahertz sensor 05, Eavesdropping on the electron: A new method for extracting data from noise 06. In a surprising finding, light can make water evaporate without heat 07. Light-powered MOFs make seawater drinkable with the flip of a switch 08. Liquid metal skins turned into power source for stretchable batteries and devices 09. Optical-fiber based single-photon light source at room temperature for next-generation quantum processing 10. Scientists […]
Bartering light for light: Scientists discover new system to control the chaotic behavior of light
Phys.org November 2, 2023 Prominent non-Hermitian phenomena include coherent perfect absorption and its generalization, reflectionless scattering modes, in which electromagnetic scattering at the input ports is suppressed due to critical coupling with the power leaked to output ports, and interference phenomena. These concepts are ideally suited to enable real-time dynamic control over absorption, scattering and radiation. However, reflectionless scattering modes have not been observed in complex photonic platforms involving open systems and multiple inputs. An international team of researchers (USA – City University of New York, Germany) demonstrated the emergence of reflectionless scattering modes in a chaotic photonic microcavity involving […]
Communing with nothingness
Nanowerk November 6, 2023 Light–matter interaction in the ultrastrong coupling regime is attracting considerable attention owing to its applications to coherent control of material properties by a vacuum fluctuation field. However, electrical access to such an ultra-strongly coupled system is very challenging. Researchers in Japan have fabricated a gate-defined quantum point contact (QPC) near the gap of a terahertz (THz) split-ring resonator (SRR) fabricated on a GaAs two-dimensional (2D) electron system. By illuminating the system with external THz radiation, the QPC showed a photocurrent spectrum which exhibited significant anticrossing that came from coupling between the cyclotron resonance of the 2D […]
A Controversial Superconductor Paper Has Finally Been Retracted by Nature
Science Alert November 8, 2023 Nature RETRACTED ARTICLE: Evidence of near-ambient superconductivity in a N-doped lutetium hydride at the request of the authors Nathan Dasenbrock-Gammon, Elliot Snider, Raymond McBride, Hiranya Pasan, Dylan Durkee, Sachith E. Dissanayake, Keith V. Lawler and Ashkan Salamat. They have expressed the view as researchers who contributed to the work that the published paper does not accurately reflect the provenance of the investigated materials, the experimental measurements undertaken, and the data-processing protocols applied. The above-named authors have concluded that these issues undermine the integrity of the published paper. In addition, and separately, concerns have been independently […]
Efficient biohybrid batteries
Science Daily October 31, 2023 Incorporating the latest advancements in microbial electrochemistry and electrochemical CO2 reduction, researchers in China have developed a super-fast charging biohybrid battery by using pure formic acid as an energy carrier. CO2 electrolyzer made it possible to use affordable anion exchange membranes and electrocatalysts that were readily accessible. The biohybrid battery required a 3-minute charging to accomplish 25-hour discharging phase. Bioconversion played a vital role in restricting both the overall Faradaic efficiency and Energy efficiency. The electrolyser was able to operate continuously for 164 hours under Gas Stand-By model, by storing N2 gas in the extraction […]
Detecting hidden defects in materials using a single-pixel terahertz sensor
Phys.org November 6, 2023 Existing terahertz inspection systems face throughput and accuracy restrictions due to their limited imaging speed and resolution. Furthermore, machine-vision-based systems using large-pixel-count imaging encounter bottlenecks due to their data storage, transmission, and processing requirements. Researchers at UCLA developed a diffractive sensor that rapidly detects hidden defects/objects within a 3D sample using a single-pixel terahertz detector, eliminating sample scanning or image formation/processing. Using deep-learning-optimized diffractive layers, the diffractive sensor could all-optically probe the 3D structural information of samples by outputting a spectrum, and directly indicated the presence/absence of hidden structures or defects. They experimentally validated this framework […]