Photon
Quantum "spooky action at a distance" travels at least 10,000 times faster than light
Quantum entanglement, one of the odder aspects of quantum theory, links the properties of particles even when they are separated by large distances. When a property of one of a pair of entangled particles is measured, the other "immediately" settles down into a state compatible with that measurement. So how fast is "immediately"? According to research by Prof. Juan Yin and colleagues at the University of Science and Technology of China in Shanghai, the lower limit to the speed associated with entanglement dynamics – or "spooky action at a distance" – is at least 10,000 times faster than light. Read More
Left to its own ways, light will follow the same path through an optical system whether the system is being used as a camera lens or as a projector. This is called time-reversal symmetry, or reciprocity. As many new applications and methods would be enabled by access to a non-reciprocal optical system, it is unfortunate that they have been so difficult to come by. But now researchers at Stanford University have discovered how to make such non-reciprocal systems by generating an effective magnetic field for photons. Read More
Australian researchers amplify quantum information using teleportation
The establishment of a worldwide quantum internet would provide individuals, businesses, organizations, and governments access to intrinsically secure communications. However, absorption of photons in transit between internet nodes can dramatically reduce the efficiency of such a quantum internet. Now a research group at Australia's (CQCCT) has invented a way to recover some of the lost quantum information by teleporting the original information to another photon. Read More
Quantum spacetime more like foam rubber than beer foam
A recent study of gamma-ray bursts by Professor Robert Nemiroff and his colleagues at Michigan Technological University provides the first strong evidence concerning the small-scale smoothness of spacetime. Oddly, this examination of the very small is accomplished by measuring a handful of gamma-rays after they traveled over ten billion light years. Read More
Faster-than-light travel observed ... of neutrinos, maybe
According to Einstein’s restricted theory of relativity, nothing can travel faster than light in a vacuum. Up until today, that had pretty much seemed to be the case, too. Early this morning, however, researchers from the Geneva-based OPERA project announced that the results from one of their recent experiments indicate that neutrinos can in fact outrun light particles. Read More
Researchers from Germany’s Max Planck Institute of Quantum Optics (MPQ) and the Swiss Ecole Polytechnique Federale de Lausanne (EPFL) have created a microresonator that produces vibrations from laser light. The device also uses one laser beam to control the intensity of another, thus making it essentially an optical transistor. The technology could have big implications in fields such as telecommunications. Read More
Quantum cryptography has been around since the 1980's but up until now only very small packets of information have been able to be encrypted at one time. Now a breakthrough that identifies the angle and rotation of photon particles is taking this technology to the next level. Read More
Silicon-based solar cells, by far the most prevalent type of solar cell available today, might provide clean, green energy but they are bulky, rigid and expensive to produce. Organic (carbon-based) semiconductors are seen as a promising way to enable flexible, lightweight solar cells that would also be much cheaper to produce as they could be “printed” in large plastic sheets at room temperature. New research from physicists at Rutgers University has strengthened hopes that solar cells based on organic semiconductors may one day overtake silicon solar cells in cost and performance, thereby increasing the practicality of solar-generated electricity as an alternative energy source to fossil fuels. Read More
Physicists from the University of Oregon have successfully changed the color of individual photons within a fiber optic cable. They were able to do so by focusing a dual-color burst of light from two lasers onto an optical cable carrying a single photon of a distinct color. Through a process known as Bragg scattering, a small amount of energy was exchanged between the laser light and the photon, causing the photon to change color. The achievement could pave the way for transferring and receiving high volumes of secured electronic data. Read More
Research has already shown that at the nanoscale, chemistry is different and the same is apparently true for light, which Engineers at Stanford University say behaves differently at scales of around a nanometer. By creating solar cells thinner than the wavelengths of light the engineers say it is possible to trap the photons inside the solar cell for longer, increasing the chance they can get absorbed, thereby increasing the efficiency of the solar cell. In this way, they calculate that by properly configuring the thicknesses of several thin layers of films, an organic polymer thin film could absorb as much as 10 times more energy from sunlight than predicted by conventional theory. Read More