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Metallic Nanostructures for Generating Exotic Forms of Light – SciTechDaily

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Multiparticle scattering in plasmonic systems. Credit: LSU

LSU Quantum researchers rearrange photon distribution to create different light sources.

For decades, scholars have believed that the quantum statistical properties of bosons are preserved in plasmonic systems, and therefore will not create different form of light.

This rapidly growing field of research focuses on quantum properties of light and its interaction with matter at the nanoscale level. Stimulated by experimental work in the possibility of preserving nonclassical correlations in light-matter interactions mediated by scattering of photons and plasmons, it has been assumed that similar dynamics underlie the conservation of the quantum fluctuations that define the nature of light sources. The possibility of using nanoscale system to create exotic forms of light could pave the way for next-generation quantum devices. It could also constitute a novel platform for exploring novel quantum phenomena.

In new findings published in Nature Communications, researchers from Louisiana State University and four collaborating universities have introduced a discovery that changes a paradigm in quantum plasmonics by demonstrating the potential of metallic nanostructures to produce different forms of light.

Their paper, “Observation of the Modification of Quantum Statistics of Plasmonic Systems,” written by collaborators from the University of Alabama in Huntsville, Tecnologico de Monterrey, Universidad Nacional Autónoma de México and Universidad Autónoma Metropolitana Unidad Iztapalapa, demonstrates that the quantum statistics of multiparticle systems are not always preserved in plasmonic platforms. It also describes the first observation of the modified quantum statistics.

Lead authors, LSU postdoctoral researcher Chenglong You and LSU graduate student Mingyuan Hong, show that optical near fields provide additional scattering paths that can induce complex multiparticle interactions.

“Our findings unveil the possibility of using multiparticle scattering to perform exquisite control of quantum plasmonic systems,” You said. “This result redirects an old paradigm in the field of quantum plasmonics where the fundamental physics uncovered in our discovery will provide a better understanding of the quantum properties of plasmonic systems, and unveil new paths to perform control of quantum multiparticle systems.”

Research pursued by the Experimental Quantum Photonics Group at LSU for the new findings was conducted in Assistant Professor Omar Magaña-Loaiza’s Quantum Photonics Laboratory.

“We engineered metallic nanostructures, fabricated in gold, to produce different kinds of light,” Hong said. “Our nanoscale platform exploits dissipative plasmonic near fields to induce and control complex interactions in many-body systems of photons. This capability allows us to control at will the quantum fluctuations of multiphoton systems.”

The possibility of engineering light with different quantum mechanical properties has enormous implications for multiple quantum technologies.

“For example, our platform enables the reduction of the quantum fluctuations of multiphoton systems to boost the sensitivity of protocols for quantum sensing,” Magaña-Loaiza said. “In our lab, we will exploit this exquisite degree of control to develop quantum simulations of light transport. This will enable the eventual design of better and more efficient solar cells.”

Reference: “Observation of the modification of quantum statistics of plasmonic systems” by Chenglong You, Mingyuan Hong, Narayan Bhusal, Jinnan Chen, Mario A. Quiroz-Juárez, Joshua Fabre, Fatemeh Mostafavi, Junpeng Guo, Israel De Leon, Roberto de J. León-Montiel and Omar S. Magaña-Loaiza, 27 August 2021, Nature Communications.
DOI: 10.1038/s41467-021-25489-4

This research was supported by the U.S. Department of Energy.

The Quantum Photonics Group in the Department of Physics and Astronomy at LSU investigates novel properties of light and their potential for developing quantum technologies. The team also conducts experimental research in the fields of quantum plasmonics, quantum imaging, quantum metrology, quantum simulation, quantum communication, and quantum cryptography.

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Oldest human footprints in North America found in New Mexico – CTV News

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WASHINGTON —
Fossilized footprints discovered in New Mexico indicate that early humans were walking across North America around 23,000 years ago, researchers reported Thursday.

The first footprints were found in a dry lake bed in White Sands National Park in 2009. Scientists at the U.S. Geological Survey recently analyzed seeds stuck in the footprints to determine their approximate age, ranging from around 22,800 and 21,130 years ago.

The findings may shed light on a mystery that has long intrigued scientists: When did people first arrive in the Americas, after dispersing from Africa and Asia?

Most scientists believe ancient migration came by way of a now-submerged land bridge that connected Asia to Alaska. Based on various evidence — including stone tools, fossil bones and genetic analysis — other researchers have offered a range of possible dates for human arrival in the Americas, from 13,000 to 26,000 years ago or more.

The current study provides a more solid baseline for when humans definitely were in North America, although they could have arrived even earlier, the authors say. Fossil footprints are more indisputable and direct evidence than “cultural artifacts, modified bones, or other more conventional fossils,” they wrote in the journal Science, which published the study Thursday.

“What we present here is evidence of a firm time and location,” they said.

Based on the size of the footprints, researchers believe that at least some were made by children and teenagers who lived during the last ice age.

David Bustos, the park’s resource program manager, spotted the first footprints in ancient wetlands in 2009. He and others found more in the park over the years.

“We knew they were old, but we had no way to date the prints before we discovered some with (seeds) on top,” he said Thursday.

Made of fine silt and clay, the footprints are fragile, so the researchers had to work quickly to gather samples, Bustos said.

“The only way we can save them is to record them — to take a lot of photos and make 3D models,” he said.

Earlier excavations in White Sands National Park have uncovered fossilized tracks left by a saber-toothed cat, dire wolf, Columbian mammoth and other ice age animals.

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

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Inspiration4 Lift Off: SpaceX Launches World’s First All-Citizen Mission in Earth’s Orbit – Illinoisnewstoday.com

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Tampa, Florida (WFLA) — SpaceX made history on Wednesday night when it launched the world’s first all-civil mission to get going from the Space Coast, Florida.

The Inspiration4 mission took off from Launch Complex 39A at NASA’s Kennedy Space Center around 8:03 pm on Wednesday. The four crew members on the SpaceX Dragon spacecraft were launched onto a reusable Falcon 9 rocket and later separated from the spacecraft and landed on the drone.

The mission’s five-hour launch window began at 8:02 EST. The window was very large, as the crew was sent to orbit the Earth rather than the International Space Station, and therefore did not have such strict time constraints.

The crew is set to travel 350 miles above the surface of the Earth, about 100 miles higher than the International Space Station.

“This is important and historic, because it’s the best time humans have been in orbit since the Hubble Space Telescope mission,” said Benjireed, SpaceX’s manned spaceflight director.

(Photo provided by SpaceX)

The crew will spend three days in orbit to participate in research experiments on human health and performance. We hope that the results of our research will apply not only to future space flight, but also to human health here on Earth.

Inspiration4’s main goal is to provide and inspire support for St. Jude Children’s Research Hospital. They want to raise $ 200 million for St. Jude in a three-day mission.

According to SpaceX, each of the four members of the crew was chosen to represent the pillars of a mission of prosperity, generosity, hope and leadership. The Inspiration 4 crew and the pillars they represent are:

  • leadership: 38 years old Jared Isaacman – Founder and CEO of Shift4Payments
  • Hope: 29-year-old Haley Arseno – Doctor assistants and childhood cancer survivors treated with St. Jude
  • Generosity: 41 years old Chris Sembroski – Lockheed Martin US Air Force veteran and aerospace employee
  • prosperity: 51 years old Dr. Cyan Proctor – Entrepreneurs, educators, trained pilots, and the active voice of the space exploration community

SpaceX trained all four crew members as commercial astronauts on Falcon 9 and Dragon spacecraft. The crew was trained in orbital mechanics, microgravity, weightlessness, other stress tests, emergency preparedness, and spacesuit training.

The mission was funded by Isaacman in a private transaction with SpaceX. Isaacman has also invested $ 100 million towards a funding target for the St. Jude mission.

Inspiration4 Lift Off: SpaceX Launches World’s First All-Citizen Mission in Earth’s Orbit

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'Flying' microchips could ride the wind to track air pollution – Yahoo Movies Canada

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Researchers have created a winged microchip around the size of a sand grain that may be the smallest flying device yet made, Vice has reported. They’re designed to be carried around by the wind and could be used in numerous applications including disease and air pollution tracking, according to a paper published by Nature. At the same time, they could be made from biodegradable materials to prevent environmental contamination. 

The design of the flyers was inspired by spinning seeds from cottonwood and other trees. Those fall slowly by spinning like helicopters so they can be picked up by the wind and spread a long distance from the tree, increasing the range of the species. 

The team from Northwest University ran with that idea but made it better, and smaller. “We think we’ve beaten biology… we’ve been able to build structures that fall in a more stable trajectory at slower terminal velocities than equivalent seeds,” said lead Professor John A. Rogers. “The other thing… was that we were able to make these helicopter flyer structures that are much smaller than seeds you would see in the natural world.”  

They’re not so small that the aerodynamics starts to break down, though. “All of the advantages of the helicopter design begin to disappear below a certain length scale, so we pushed it all the way, as far as you can go or as physics would allow,” Rogers told Vice. “Below that size scale, everything looks and falls like a sphere.”

The devices are also large enough to carry electronics, sensors and power sources. The team tested multiple versions that could carry payloads like antenna so that they could wireless communicate with a smartphone or each other. Other sensors could monitor things like air acidity, water quality and solar radiation. 

The flyers are still concepts right now and not ready to deploy into the atmosphere, but the team plans to expand their findings with different designs. Key to that is the use of biodegradable materials so they wouldn’t persist in the environment. 

“We don’t think about these devices… as a permanent monitoring componentry but rather temporary ones that are addressing a particular need that’s of finite time duration,” Rogers said. “That’s the way that we’re envisioning things currently: you monitor for a month and then the devices die out, dissolve, and disappear, and maybe you have to redeploy them.”

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