Diamond-based imaging system uses magnetic resonance of electrons to detect charged atoms.
This summer, an ice chest-sized box will fly to the International Space Station, where it will create the coolest spot in the universe.
Inside that box, lasers, a vacuum chamber and an electromagnetic “knife” will be used to cancel out the energy of gas particles, slowing them until they’re almost motionless. This suite of instruments is called the Cold Atom Laboratory (CAL), and was developed by NASA’s Jet Propulsion Laboratory in Pasadena, California. CAL is in the final stages of assembly at JPL, ahead of a ride to space this August on SpaceX CRS-12.
Its instruments are designed to freeze gas atoms to a mere billionth of a degree above absolute zero. That’s more than 100 million times colder than the depths of space.
Controlled nuclear fusion has been a holy grail for physicists who seek an endless supply of clean energy. Scientists at Rice University, the University of Illinois at Urbana-Champaign and the University of Chile offered a glimpse into a possible new path toward that goal.
Their report on quantum-controlled fusion puts forth the notion that rather than heating atoms to temperatures found inside the sun or smashing them in a collider, it might be possible to nudge them close enough to fuse by using shaped laser pulses: ultrashort, tuned bursts of coherent light.
Authors Peter Wolynes of Rice, Martin Gruebele of Illinois and Illinois alumnus Eduardo Berrios of Chile simulated reactions in two dimensions that, if extrapolated to three, might just produce energy efficiently from deuterium and tritium or other elements.
One of the most fundamental tenets of modern physics is that in a perfect vacuum — a place entirely devoid of matter — no friction can possibly exist, because empty space cannot exert a force on objects travelling through it.
But despite the conventional wisdom, physicists in the UK discovered that a decaying atom travelling through a complete vacuum would experience a friction-like force, and now they’ve figured out how this reinforces — rather than breaks — Einstein’s theory of general relativity.
“We spent ages searching for the mistake in the calculation and spent even more time exploring other strange effects until we found this (rather simple) solution,” one of the team, Matthias Sonnleitner from the University of Glasgow told Lisa Zyga at Phys.org.
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A Yale-led team has produced one of the highest-resolution maps of dark matter ever created, offering a detailed case for the existence of cold dark matter—sluggish particles that comprise the bulk of matter in the universe.
The dark matter map is derived from Hubble Space Telescope Frontier Fields data of a trio of galaxy clusters that act as cosmic magnifying glasses to peer into older, more distant parts of the universe, a phenomenon known as gravitational lensing.
Yale astrophysicist Priyamvada Natarajan led an international team of researchers that analyzed the Hubble images. “With the data of these three lensing clusters we have successfully mapped the granularity of dark matter within the clusters in exquisite detail,” Natarajan said. “We have mapped all of the clumps of dark matter that the data permit us to detect, and have produced the most detailed topological map of the dark matter landscape to date.”
Colloidal particles, used in a range of technical applications including foods, inks, paints, and cosmetics, can self-assemble into a remarkable variety of densely-packed crystalline structures. For decades, though, researchers have been trying to coax colloidal spheres to arranging themselves into much more sparsely populated lattices in order to unleash potentially valuable optical properties. These structures, called photonic crystals, could increase the efficiency of lasers, further miniaturize optical components, and vastly increase engineers’ ability to control the flow of light.
A team of engineers and scientists from the NYU Tandon School of Engineering Department of Chemical and Biomolecular Engineering, the NYU Center for Soft Matter Research, and Sungkyunkwan University School of Chemical Engineering in the Republic of Korea report they have found a pathway toward the self-assembly of these elusive photonic crystal structures never assembled before on the sub-micrometer scale (one micrometer is about 100 times smaller than the diameter of a strand of human hair).
The research, which appears in the journal Nature Materials, introduces a new design principle based on preassembled components of the desired superstructure, much as a prefabricated house begins as a collection of pre-built sections. The researchers report they were able to assemble the colloidal spheres into diamond and pyrochlore crystal structures — a particularly difficult challenge because so much space is left unoccupied.
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If you aren’t already, you’re likely soon to find yourself looking forward to the day when quantum computers will replace regular computers for every day use. The computing power of quantum computers is immense compared to what regular desktops or laptops can do. The downside is, current quantum computing technology are limited by the bulky frameworks and extreme conditions they require in order to function.
Quantum computers need specialized setups in order to sustain and keep quantum bits — the heart of quantum computing — working. These “qubits” are particles in a quantum state of superposition, which allows them to encode and transmit information as 0s and 1s simultaneously. Most computers run on binary bit systems which use either 0s or 1s. Since quantum computers can use both at the same time, they can process more information faster. That being said, Sustaining the life of qubits is particularly difficult, but researchers are investigating quantum computing studies are trying to find ways to prolong the life of qubits using various techniques.
How do molecules rotate in a solvent? Answering this question is complicated, since molecular rotation is perturbed by a very large number of surrounding atoms. For a long time, large-scale computer simulations have been the main approach to model molecule-solvent interactions. However, they are extremely time consuming and sometimes infeasible. Now, Mikhail Lemeshko from the Institute of Science and Technology Austria (IST Austria) has proven that angulons—a certain type of quasiparticle he proposed two years ago—do, in fact, form when a molecule is immersed in superfluid helium. This offers a quick and simple description for rotation of molecules in solvents.
In physics, the concept of quasiparticles is used as a technique to simplify the description of many-particle systems. Namely, instead of modeling strong interactions between trillions of individual particles, one identifies building blocks of the system that are only weakly interacting with one another. These building blocks are called quasiparticles and might consist of groups of particles. For example, to describe air bubbles rising up in water from first principles, one would need to solve an enormous set of equations describing the position and momentum of each water molecule. On the other hand, the bubbles themselves can be treated as individual particles—or quasiparticles—which drastically simplifies the description of the system. As another example, consider a running horse engulfed in a cloud of dust. One can think of it as a quasiparticle consisting of the horse itself and the dust cloud moving along with it.
I remember a year ago when this 1st came out; nice they are highlighting 1 yr later as a reminder.
British scientists David Thouless, Duncan Haldane and Michael Kosterlitz won this year’s Nobel Prize in Physics “for theoretical discoveries of topological phase transitions and topological phases of matter”. The reference to “theoretical discoveries” makes it tempting to think their work will not have practical applications or affect our lives some day. The opposite may well be true.
To understand the potential, it helps to understand the theory. Most people know that an atom has a nucleus in the middle and electrons orbiting around it. These correspond to different energy levels. When atoms group into substances, all the energy levels of each atom combine into bands of electrons. Each of these so-called energy bands has space for a certain number of electrons. And between each band are gaps in which electrons can’t flow.
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