Phys.org September 28, 2021 After theoretical and computer modeling studies an international team of researchers (France, USA – Lawrence Livermore National Laboratory) proposed a scheme to explore regimes of strong-field quantum electrodynamics (SF QED) otherwise unattainable with the currently available laser technology. The scheme relies on relativistic plasma mirrors curved by radiation pressure to boost the intensity of petawatt-class laser pulses by Doppler effect and focus them to extreme field intensities. They showed that very clear SF QED signatures could be observed by placing a secondary target where the boosted beam is focused. This may finally crack the elusive physics […]
Disrupting Exploitable Patterns in Software to Make Systems Safer
DARPA News September 22, 2021 The Hardening Development Toolchains Against Emergent Execution Engines (HARDEN) program seeks to give developers a way to explore novel theories and approaches and develop practical tools to anticipate, isolate, and mitigate emergent behaviors in computing systems throughout the entire software development lifecycle (SDLC). The program aims to create mitigation approaches that go well beyond patching. It will also focus on validating the generated approaches by applying broad theories and generic tools to concrete technological use cases of general-purpose integrated software systems…read more. More information on the program
Flexible, stretchable battery capable of moving smoothly like snake scales
Nanowerk September 28, 2021 Researchers in South Korea have made a structure with individual, overlapping units, similar to snake scales that can be used to construct shape-morphing batteries for untethered soft robots. They created it by folding well-defined, two-dimensional patterns with cutouts, the folding lines mimicking the hinge structure of snakeskin, enabling stable deformations without mechanical damage to rigid cells. The structure is applied to a stretchable Li-ion battery, constructed to form an arrangement of electrically interconnected, hexagonal pouch cells. Simulation confirmed that the battery maintains its performance under dynamic deformation with a 90% stretching ratio and 10-mm-radius bending curve, […]
Implementing a 46-node quantum metropolitan area network
Phys.org September 30, 2021 To achieve a practical quantum network, we need to overcome several challenges including realizing versatile topologies for large scales, simple network maintenance, extendable configuration, and robustness to node failures. To this end, an international team of researchers (China, Germany) developed a field operation of a quantum metropolitan-area network with 46 nodes and showed that all these challenges can be overcome with cutting-edge quantum technologies. They used different topological structures and continuously ran the network for 31 months, by employing standard equipment for network maintenance with an extendable configuration. QKD pairing and key management was done with […]
Microscopic metavehicles powered by nothing but light
Science Daily September 28, 2021 Optical tweezers were developed using a highly focused laser beam to control and maneuver tiny particles. An international team of researchers (Sweden, Russia) has shown that even unfocused light can be used to maneuver microscopic particles in a controlled manner by developing “metavehicle” consisting of a tiny particle coated with metasurface. They used the forces resulting from the light’s change in momentum control the meta-surface. By placing the metavehicle at on the bottom of the water dish, they used loosely focused laser to direct a plane wave of light onto them moving the metavehicle in […]
New technique speeds measurement of ultrafast pulses
Science Daily September 24, 2021 Based on the spatio-temporal duality of light pulses, an international team of researchers (USA – University of Rochester, China, Canada) has developed a time-domain single-pixel imaging technique that detects 5 femtojoule ultrafast light pulses with a temporal sampling size down to 16 femtoseconds. The technique can also be combined with single-pixel imaging to create a computational hyperspectral imaging system. The system can greatly speed up the detection and analysis of images at broad frequency bands which could be especially useful for medical applications. According to the researchers by coupling their technique with single pixel imaging […]
Research reveals potential of an overlooked climate change solution
Phys.org September 27, 2021 Carbon dioxide removal has an increasingly well-established research agenda and technological foundation. There is no framework for methane removal. While some removal technologies are being developed, modelling of their impacts is limited. An international team of researchers (USA – Stanford University, UC Irvine, University of Pennsylvania, Germany, UK, Canada, France) conducted the first simulations using a methane emissions-driven Earth System Model to quantify the climate and air quality co-benefits of methane removal, including different rates and timings of removal. They defined a novel metric, the effective cumulative removal, and used it to show that each effective […]
Researchers integrate optical devices made of multiple materials onto single chip
Science Daily September 29, 2021 An international team of researchers (UK, Italy, Australia) has developed transfer printing process and demonstrated its ability to place devices made of multiple materials on a single chip, all integrated within a footprint similar in size to the devices themselves. The method is based on reversible adhesion in which a device is picked up and released from its growth substrate and placed onto a new surface. The process uses a soft polymer stamp mounted on a robotic motion control stage to pick up an optical device from the substrate on which it was made. When […]
Scientists create material that can both move and block heat
Science Daily September 30, 2021 An international team of researchers (USA – University of Chicago, University of Illinois, Cornell University, Sweden) stacked ultra-thin layers of crystalline sheets on top of each other, but rotated each layer slightly, creating a material with atoms that are aligned in one direction but not in the other. They measured the results and found that a microscopic wall made of this material was extremely good at preventing heat from moving between compartments. They could transport heat along the wall very easily. Making computer chips smaller creates a high-power density environment. But if we can use […]
Tiny lasers acting together as one: Topological vertical cavity laser arrays
Phys.org September 24, 2021 Vertical-Cavity Surface-Emitting Lasers (VCSEL) device has miniscule size of only a few microns, which sets a stringent limit on the output power it can generate. An international team of researchers (Israel, Germany) utilized the concepts of topological photonics with VCSELs that emit light vertically, while the topological process responsible for the mutual coherence and locking of the VCSELs occurs in the plane of the chip. It resulted in a powerful but very compact and efficient laser, not limited by a number of VCSEL emitters, and undisturbed by defects or altering temperatures. The topological principle of this […]