Vacunacionadultos

Scientists stuff graphene with light

No losses: Scientists stuff graphene with light
Credit: Daria Sokol/MIPT

Physicists from MIPT and Vladimir State University, Russia, have converted light energy into surface waves on graphene with nearly 90% efficiency. They relied on a laser-like energy conversion scheme and collective resonances. The paper was published in Laser & Photonics Reviews.


Manipulating light at the nanoscale is a task crucial for being able to create ultracompact devices for optical energy conversion and storage. To localize light on such a small scale, researchers convert optical radiation into so-called surface plasmon-polaritons. These SPPs are oscillations propagating along the interface between two materials with drastically different refractive indices—specifically, a metal and a dielectric or air. Depending on the materials chosen, the degree of surface wave localization varies. It is the strongest for light localized on a material only one atomic layer thick, because such 2-D materials have high refractive indices.

The existing schemes for converting light to SPPs on

Read More

Truffle munching wallabies shed new light on forest conservation

Truffle munching wallabies shed new light on forest conservation
Credit: Todd F Elliott

Feeding truffles to wallabies may sound like a madcap whim of the jet-setting elite, but it may give researchers clues to preserving remnant forest systems.


Edith Cowan University researcher Dr. Melissa Danks led an investigation into how swamp wallabies spread truffle spores around the environment, and results demonstrate the importance of these animals to the survival of the forest.

“There are thousands of truffle species in Australia and they play a critical role in helping our trees and woody plants to survive,” she said.

“Truffles live in a mutually beneficial relationship with these plants, helping them to uptake water and nutrients and defense against disease. Unlike mushrooms where spores are dispersed through wind and water from their caps, truffles are found underground with the spores inside an enclosed ball—they need to be eaten by an animal to move their spores.”

Dr. Danks and colleagues at the

Read More

Destiny 2 Beyond Light – Salvation’s Grip Exotic Quest Guide

There’s a lot to do in Destiny 2’s Beyond Light expansion. While the campaign focuses on defeating the Fallen Kell Eramis and her House of Salvation underlings, it also pushes you to use Stasis, Destiny 2’s new power, and to fully unlock the potential of your new subclass. Once you’ve worked far enough through the story, you can start on your first Exotic quest, called The Stasis Prototype. It’ll send you on a lengthy mission to steal a Stasis-firing grenade launcher, Salvation’s Grip, from the Fallen and add it to your arsenal.

Here’s everything you need to know about unlocking Salvation’s Grip quickly and efficiently, so you can get on with the story of Beyond Light.

Complete The First Part Of The Beyond Light Campaign

First, play through the new story missions in Beyond Light. Fight through to defeat Eramis, continue with the Exo Stranger to unlock Stasis abilities, and

Read More

Destiny 2 Beyond Light – Where To Find Entropic Shards To Earn Your Stasis Aspect

Working through the story campaign of Beyond Light, Destiny 2’s latest expansion, will earn you the new Stasis ability–a power that lets you slow and freeze enemies to take them out of the fight and deal massive damage. To get the most out of the new abilities, though, you’ll need Aspects, equippable mods that give your Stasis subclass new abilities.

Your first Aspect comes from a quest late in the Beyond Light campaign, and you’ll need to hunt down collectibles called Entropic Shards to complete it. We’ve run down everything you need to do and to know in order to unlock your first Stasis Aspect, while also detailing the locations of every Entropic Shard currently found on Europa.

Unlock Stasis Aspects By Getting The Aspect Of Control Quest

First, work your way through the Beyond Light campaign. Defeat Eramis and continue on the Exo Stranger’s Born in Darkness quests until

Read More

Research produces intense light beams with quantum correlations

Research produces intense light beams with quantum correlations
Potential applications of research conducted at the University of São Paulo include high-precision metrology and information encoding (pump laser for production of quantum-correlated light beams). Credit: Marcelo Martinelli / IF-USP

The properties of quantum states of light are already leveraged by such highly sophisticated leading-edge technologies as those of the latest sensitivity upgrades to LIGO, the Laser Interferometer Gravitational-Wave Observatory, deployed to detect gravitational waves since September 2015, or the encryption keys used for satellite on-board security.


Both solutions use crystals as noise-free optical amplifiers. However, the use of atomic vapors has been considered a more efficient alternative that enhances the accessibility of non-classical light states.

“We show that oscillators based on these atomic amplifiers can generate intense beams of light with quantum correlations,” said Marcelo Martinelli, a researcher in the University of São Paulo’s Physics Institute (IF-USP). Martinelli is a co-author of an article published in Physical Review Letters

Read More

3D Scanning Sheds Light On 2-Million-Year-Old Skull

Sometimes it takes the very latest technology to answer some of the oldest questions. This week, researchers announced the discovery of an incredibly rare, 2-million-year-old skull in South Africa that is a cousin species to “Homo erectus,” the famous extinct archaic human from the Pleistocene era.

The only problem? The cranium, which was encased in a significant amount of sediment, was in more than 300 pieces. Fortunately, the team was able to turn to the latest 3D-scanning technology, a tool called the Artec Space Spider, to painstakingly reconstruct the skull. The process, which took hundreds of hours, helped them discover insights they may not have otherwise come to light — such as clues in the teeth that suggest the subject’s likely diet.

“During the process of removing the individual pieces from the sediment, I scanned the cranium so that if any pieces unexpectedly dislodged, there was a high resolution of

Read More

The first demonstration of phase-matching between an electron wave and a light wave

The first demonstration of phase-matching between an electron wave and a light wave
Computer simulation of the electron-light interaction. The laser light (red-blue wave pattern) interacts with the electron wavefunction (elongated sphere) that passes nearby. This unique experimental setup assures that the electron exchanges energy with the laser in a resonant manner – achieving the precise conditions of the Cherenkov effect. Credit: Dahan et al.

While researchers have conducted countless studies exploring the interaction between light waves and bound electron systems, the quantum interactions between free electrons and light have only recently become a topic of interest within the physics community. The observation of free electron-light interactions was facilitated by the discovery of a technique known as photon-induced near-field electron microscopy (PINEM).


Although some experiments using PINEM methods have yielded interesting results, the free-electron light interactions observed so far are fairly weak. This is mainly because PINEM methods gather localized and near-field measurements without addressing the velocity mismatch between free electrons and light,

Read More

Bending light to engineer improved optical devices and circuits

‘Bending’ light to engineer improved optical devices and circuits
Irfan Khan, electrical engineering Ph.D. student. Credit: University of Notre Dame

Rainbows are formed when light bends—or refracts—as it enters and exits a water droplet. The amount that the light bends depends on the color of the light, resulting in white light being separated into a beautiful spectrum of colors. The index of refraction, one of the tools that optical engineers use to control light, describes the interaction between light and matter.


Recently, materials that have an index of refraction that vanishes have gained significant interest across the scientific and engineering communities. These materials, called epsilon-near-zero (ENZ) materials, show great promise for applications in imaging small objects, detecting minute concentrations of targeted molecules (e.g., explosives, toxic chemicals, pollutants) and enabling a new generation of optical devices and circuits.

A team from the University of Notre Dame in collaboration with researchers at the University of Texas at Austin, Cornell University and

Read More

Researchers decode thermal conductivity with light

Clemson researchers decode thermal conductivity with light
Collaborative research by (from left) Sriparna Bhattacharya, Prakash Parajuli and Apparao Rao has been published in the journal Advanced Science. Credit: College of Science

Groundbreaking science is often the result of true collaboration, with researchers in a variety of fields, viewpoints and experiences coming together in a unique way. One such effort by Clemson University researchers has led to a discovery that could change the way the science of thermoelectrics moves forward.


Graduate research assistant Prakash Parajuli; research assistant professor Sriparna Bhattacharya; and Clemson Nanomaterials Institute (CNI) Founding Director Apparao Rao (all members of CNI in the College of Science’s Department of Physics and Astronomy) worked with an international team of scientists to examine a highly efficient thermoelectric material in a new way—by using light.

Their research has been published in the journal Advanced Science and is titled “High zT and its origin in Sb-doped GeTe single crystals.”

“Thermoelectric materials

Read More

Scientists work to shed light on Standard Model of particle physics

Scientists work to shed light on Standard Model of particle physics
Typical magnetic field variations as mapped by the trolley at different positions in the Muon g-2 experiment’s storage ring, shown at the parts-per-million level. Credit: Argonne National Laboratory.

As scientists await the highly anticipated initial results of the Muon g-2 experiment at the U.S. Department of Energy’s (DOE) Fermi National Accelerator Laboratory, collaborating scientists from DOE’s Argonne National Laboratory continue to employ and maintain the unique system that maps the magnetic field in the experiment with unprecedented precision.


Argonne scientists upgraded the measurement system, which uses an advanced communication scheme and new magnetic field probes and electronics to map the field throughout the 45-meter circumference ring in which the experiment takes place.

The experiment, which began in 2017 and continues today, could be of great consequence to the field of particle physics. As a follow-up to a past experiment at DOE’s Brookhaven National Laboratory, it has the power to affirm

Read More