Phys.org August 19, 2019 Researchers at Purdue University have developed a unified perspective of unidirectional topological edge waves in nonreciprocal media. They focused on the inherent role of photonic spin in nonreciprocal gyroelectric media, i.e. magnetized metals or magnetized insulators. Hamiltonian approach predicts the existence of a third distinct class of Maxwellian edge wave exhibiting topological protection. This occurs in an intriguing topological bosonic phase of matter, fundamentally different from any known electronic or photonic medium. The goal of their paper is to discuss the three foundational classes of edge waves in a unified perspective while providing in-depth derivations, taking […]
Tag Archives: Emerging technology
In the future, this electricity-free tech could help cool buildings in metropolitan areas
EurekAlert August 5, 2019 An international team of researchers (University of Buffalo, University of Wisconsin, Saudi Arabia, China) fabricated an inexpensive planar polydimethylsiloxane (PDMS)/metal thermal emitter thin film structure using a fast solution coating process that is scalable for large-area manufacturing. The spectral-selective structure was designed and implemented to suppress the solar input and control the divergence of the thermal emission beam enhancing the directionality of the thermal emissions, so the emitter’s cooling performance was less dependent on the surrounding environment. In tests under different environmental conditions, temperature reductions of 9.5 °C and 11.0 °C in the laboratory and outside environment, respectively, […]
Quantum light sources pave the way for optical circuits
Science Daily August 1, 2019 The ability to tailor quantum emitters via site-selective defect engineering is essential for realizing scalable architectures. However, a major difficulty is that defects need to be controllably positioned within the material. An international team of researchers (Germany, USA – SUNY Buffalo, Japan) has overcome this challenge by controllably irradiating monolayer MoS2 using a sub-nm focused helium ion beam to deterministically create defects. Subsequent encapsulation of the ion exposed MoS2 flake with high-quality hBN reveals spectrally narrow emission lines that produce photons in the visible spectral range. The new method allows for a multitude of applications in […]
Laser solitons: Theory, topology and potential applications
Science Daily July 31, 2019 Solitons have found applications in data transmission but even these gradually dissipate unless the medium they travel through has ultra-low absorbance. In computer simulations researchers in Russia found that suggesting that it was theoretically possible to produce a stable soliton in a wide-aperture laser if it was stabilised by external radiation. Beginning from geometrically one-dimensional and turning to two-dimensional and then to three-dimensional solitons they demonstrated the evolution of the features. When the remaining questions are answered, the stability of these solitons and their topology suggest potential applications in storing digital information…read more. TECHNICAL ARTICLE
Developing technologies that run on light
Eurekalert July 24, 2019 Researchers at Stanford University designed arrays of ultra-thin silicon disks that work in pairs to trap the light and enhance its spiraling motion until it finds its way out. This results in high transmission in the forward direction. When illuminated in the backwards direction, the acoustic vibrations spin in the opposite direction and help cancel out any light trying to exit. Theoretically, there is no limit to how small this system could be. According to the researchers efficient photonic diodes is paramount to enabling next-generation computing, communication and even energy conversion technologies. The increased speed and […]
Graphene and nanotube mesh filters salt from water
Physics World June 24, 2019 Porous graphene sheets have excellent filtration capabilities and can block most ions, but their fragility limits their scale-up beyond laboratory demonstrations. An international team of researchers (China, USA – UCLA) has developed a way to create centimetre-sized sheets of porous graphene that do not suffer from the effects of defects. This was done by depositing a mesh-like network of single-walled carbon nanotubes on top of a graphene sheet, which essentially reinforces the material and blocks the spread of cracks and tears. Then the pores are etched in the material to create a desalination membrane. When […]
New property of light discovered
Phys.org June 28, 2019 An international team of researchers (Spain, USA – University of Colorado) has discovered a new property of light—self-torque. Their experiments involved firing two lasers at a cloud of argon gas—doing so forced the beams to overlap, and they joined and were emitted as a single beam from the other side of the argon cloud. The result was a type of vortex beam. Then they changed the the orbitatl momentum so that the lasers had different orbital angular momentum and they were slightly out of sync. This resulted in a beam that looked like a corkscrew with […]
Building the tools of the next manufacturing revolution
MIT News June 17, 2019 In partnership with industry, researchers at MIT are developing advanced materials — new types of polymers, nanocomposites, and metal alloys — and the development of novel machines and processes that use and shape materials, such as high-speed 3-D printing, roll-to-roll graphene growth, and manufacturing techniques for low-cost sensors and electronics. Leveraging advances in computation, digitization, and automation, the group sees the potential for 3-D printing to dramatically streamline and speed up global supply chains. They are also pursuing a series of projects related to carbon nanotubes, exploring ways to form nanotubes into advanced wires, fibers, […]
Europe Has Invested €1 Billion Into Graphene—But For What?
IEEE Spectrum June 3, 2019 Six years ago, the EU embarked on an ambitious project to create a kind of Silicon Valley for graphene. Over 10 years to push graphene into commercial markets the project, Graphene Flagship would leverage €1 billion. In the past six years, the Graphene Flagship has spawned nine companies and 46 new graphene-based products. Despite these achievements, there remains a sense among critics that the wonder material has not lived up to expectations and the Flagship’s efforts have not done much to change that perception…read more.
Unveiling technologies for future launch vehicles
Phys.org June 7, 2019 ESA safeguards Europe’s guaranteed access to space through its Future Launchers Preparatory Programme (FLPP) which weighs up the opportunities and risks of different launch vehicle concepts and associated technologies and defines the concepts and requirements for new space transportation systems and services. Its demonstrators and studies hone emerging technologies to give Europe’s rocket builders a valuable head-start as they begin the demanding work of turning the chosen design into reality. Technologies are selected on their potential to reduce cost, improve performance, improve reliability, or on their ability to fulfil the specific needs of an identified system, […]