Lifeboat Foundation

Physicists from Paderborn University have developed a novel concept for generating individual photons—tiny particles of light that make up electromagnetic radiation—with tailored properties, the controlled manipulation of which is of fundamental importance for photonic quantum technologies. The findings have now been published in the journal Nature Communications.

Professor Artur Zrenner, head of the “nanostructure optoelectronics” research group, explains how tailored desired states have so far posed a challenge: “Corresponding sources are usually based on light emissions from individual semiconductor quantum emitters, which generate the photons. Here, the properties of the emitted photons are defined by the fixed properties of the quantum emitter, and can therefore not be controlled with full flexibility.”

To get around the problem, the scientists have developed an all-optical, non-linear method to tailor and control single photon emissions. Based on this concept, they demonstrate laser-guided energy tuning and polarization control of photons (i.e., the light frequency and direction of oscillation of electromagnetic waves).

A new publication in Opto-Electronic Advances overviews dynamic metasurfaces and metadevices empowered by graphene.

Metasurfaces, artificial subwavelength structured interfaces, exhibit unprecedented capabilities to manipulate electromagnetic (EM) waves ranging from visible to terahertz and microwave frequencies.

In the past decade, static metasurfaces and metadevices have been researched extensively. Due to the passive nature of building blocks in general made of metals and/or dielectrics, however, their functionalities cannot be actively tuned in situ after fabrication, which seriously impedes their application scenarios such as varifocal lens, dynamic holography, and beam steering in LiDAR. Motivated by those significant requirements, scientists have struggled for years to improve the dynamical tunability of metasurfaces, and introducing active materials or components into the passive metasurfaces has been proposed as the first thought strategy.

Breakthrough hints other cells in central nervous system, such as the brain, could be restored.

They aren’t going backward — we’re just going forward. Our orbit to the Sun makes us closer to our large adult sons.

Though Boeing may redesign the capsule’s problematic valves before a crewed flight.

With Boeing’s next Starliner crew capsule launch attempt fast approaching, the company is considering redesigning the capsule’s propulsion valves, due to issues that have so far stopped the company from launching crewed flights to the ISS and competing with SpaceX, a report from *CNBC* reveals.

Boeing is developing the Starliner spacecraft thanks to a roughly $5 billion contract it was awarded under NASA’s Commercial Crew program. The next launch attempt, called OFT-2, is scheduled for next Thursday, May 19.

Continue reading “Boeing considers redesigning problematic valve that has kept Starliner from flying NASA astronauts” »

Alpha particles are also known as alpha radiation.

Alpha particles, also known as alpha radiation, are the star players in the game of alpha decay — here’s everything you need to know.

While many other companies in the industry are focusing on designing and developing hydrogen-fueled aircraft from scratch, ZeroAvia is gearing up to test its retrofitted Dornier 228 this summer.

The company has partnered with its strategic investor, Shell, to design and build two commercial-scale mobile hydrogen refuelers for use at ZeroAvia’s research and development site in Hollister, California. At ZeroAvia’s test facility in Hollister, Shell will also provide compressed, low-carbon hydrogen supply to the facility and other locations in the Western U.S.

This strategic collaboration will support the development of ZeroAvia’s flight testing program in the U.S. following the arrival of its second Dornier 228 at Hollister last month and will advance the company’s Hydrogen Airport Refueling Ecosystem (HARE) on a larger scale.