We now know the mass of an axion, which means we might be able to prove dark matter does indeed exist.
Read more
Category: particle physics – Page 556
Researchers at the Indian Institute of Science Education and Research (IISER) in Kolkata, India, have for the first time implemented a bio-waste-derived electrode as cathode in a quantum-dot-sensitized solar cell.
“The materials to be used as cathode in quantum dot solar cells need to be highly catalytic and electrically conducting to facilitate the electron transfer processes,” explains Professor Sayan Bhattacharyya from the Department of Chemical Sciences at IISER. He adds that the lamellar structure of human hair is likely responsible for the graphene-like sheets in the transformed graphitic porous carbon. “Secondly,” he continues, “since hair contains keratin and other amino acids, carbonizing the acid-digested hair under inert conditions likely retains the nitrogen and sulphur hetero-atoms, which are useful to enhance the catalytic propensity of the produced carbon.”
As the professor explains, the idea behind this research project was to use a bio-waste resource like hair in future energy technologies to achieve a win-win situation — i.e., “A smart way to address environmental concerns and also to produce cheaper devices.”
Read more
New method for creating smaller switches for QC identified and making smaller and more efficient QC systems possible.
Edmonton nanotechnology researchers working with atom-sized materials have made a breakthrough that could lead to smaller, ultraefficient computers.
The team, led by Robert Wolkow, together with collaborators at the Max Planck Institute in Hamburg, have developed a way to create atomic switches for electricity nearly 100 times smaller than the smallest switches, or transistors, on the market today. Their findings appeared in the Oct. 26 edition of the scientific publication Nature Communications.
“What we’re showing in this new paper is one part in a bigger scheme … that allows us to make ultralow power consuming electronic devices,” said Wolkow, a physics professor at the University of Alberta and the principal research officer at Edmonton’s National Institute for Nanotechnology. He’s also chief technology officer at spinoff company Quantum Silicon Inc.
Patches of chain-like molecules placed across nanoscale particles can radically transform the optical, electronic, and magnetic properties of particle-based materials. Understanding why depends critically on the three-dimensional features of these “polymer nano-patches”—which are tantalizingly difficult to reveal at a scale spanning just billionths of a meter.
Now, scientists have used cutting-edge electron tomography techniques—a process of 3D reconstructive imaging —to pinpoint the structure and composition of the polymer nano-patches. The results, published earlier this month in the journal Nature, “lay the foundation for new nanoscale architectures that could potentially enhance technologies such as self-assembled solar cells and catalysts,” said lead author Eugenia Kumacheva of the University of Toronto.
The scientists tracked the patches formed by different synthetic polymers—versatile and common compounds used in everything from plastics to electronics —on the surface of gold nanospheres thousands of times smaller than the width of a single human hair. To visualize the elusive surface structures, Kumacheva and her team turned to cutting-edge facilities at the Center for Functional Nanomaterials (CFN), a U.S. Department of Energy (DOE) Office of Science User Facility at DOE’s Brookhaven National Laboratory.
Read more
Abstract: In 1959 renowned physicist Richard Feynman, in his talk “Plenty of Room at the Bottom,” spoke of a future in which tiny machines could perform huge feats. Like many forward-looking concepts, his molecule and atom-sized world remained for years in the realm of science fiction.
And then, scientists and other creative thinkers began to realize Feynman’s nanotechnological visions.
In the spirit of Feynman’s insight, and in response to the challenges he issued as a way to inspire scientific and engineering creativity, electrical and computer engineers at UC Santa Barbara have developed a design for a functional nanoscale computing device. The concept involves a dense, three-dimensional circuit operating on an unconventional type of logic that could, theoretically, be packed into a block no bigger than 50 nanometers on any side.
Read more
Quantum theory is strange and counterintuitive, but it’s very precise. Lots of analogies and broad concepts are presented in popular science trying to give an accurate description of quantum behavior, but if you really want to understand how quantum theory (or any other theory) works, you need to look at the mathematical details. It’s only the mathematics that shows us what’s truly going on.
Mathematically, a quantum object is described by a function of complex numbers governed by the Schrödinger equation. This function is known as the wavefunction, and it allows you to determine quantum behavior. The wavefunction represents the state of the system, which tells you the probability of various outcomes to a particular experiment (observation). To find the probability, you simply multiply the wavefunction by its complex conjugate. This is how quantum objects can have wavelike properties (the wavefunction) and particle properties (the probable outcome).
No, wait. Actually a quantum object is described by a mathematical quantity known as a matrix. As Werner Heisenberg showed, each type of quantity you could observe (position, momentum, energy) is represented by a matrix as well (known as an operator). By multiplying the operator and the quantum state matrix in a particular way, you get the probability of a particular outcome. The wavelike behavior is a result of the multiple connections between states within the matrix.
Read more
To all those who said it couldn’t happen for another 10+ years; this article is definitely for you.
Robert Wolkow, University of Alberta physics professor and the Principal Research Officer at Canada’s National Institute for Nanotechnology, has developed a technique to switch a single-atom channel.
What does it all mean? With applications for practical systems like silicon semi-conductor electronics, it means smaller, more efficient, more energy-conserving computers, as just one example of the technology revolution that is unfolding right before our very eyes (if you can squint that hard).
Read more
Just WOW!
PULLMAN, Wash., Oct. 26 — Washington State University and NASA scientists are set to begin an investigation into the strange world of quantum physics on the International Space Station.
WSU physicists Peter Engels and Maren Mossman are part of a team studying the behavior of atoms laser-cooled to temperatures just a few billionths of a degree above absolute zero, the point where they behave like one wave of discrete particles.
On Earth, the unavoidable presence of gravity makes it difficult to conduct unperturbed observations of this this super-cooled substance – called a Bose-Einstein condensate – and the laws of quantum physics that govern its wave-like behavior.
Drug discovery is a long and difficult process that requires a comprehensive understanding of the molecular structures of compounds under investigation. It’s difficult to have an idea of the precise shape of complex molecules such as proteins, but researchers at University of Melbourne in Australia have come up with a way of seeing the location of individual atoms within biomolecules.
Using quantum bits, most notably utilized in quantum computer research, the investigators offer a way of producing a magnetic resonance sensor and a magnetic field gradient that can work as a tiny MRI machine. The machine would have the resolution capable of seeing single atoms components of larger molecules. This MRI machine has yet to be actually built, but the steps have been laid out based on comprehensive theoretical work. If it proves successful in practice, the technology may overcome current imaging techniques that rely on statistical averages and don’t work well on molecules that don’t crystallize well.
“In a conventional MRI machine large magnets set up a field gradient in all three directions to create 3D images; in our system we use the natural magnetic properties of a single atomic qubit,” said lead author of the research Viktor Perunicic. “The system would be fabricated on-chip, and by carefully controlling the quantum state of the qubit probe as it interacts with the atoms in the target molecule, we can extract information about the positions of atoms by periodically measuring the qubit probe and thus create an image of the molecule’s structure.”
Read more