Lifeboat Foundation

Light and sound waves are at the basis of energy and signal transport and fundamental to some of our most basic technologies—from cell phones to engines. Scientists, however, have yet to devise a method that allows them to store a wave intact for an indefinite period of time and then direct it toward a desired location on demand. Such a development would greatly facilitate the ability to manipulate waves for a variety of desired uses, including energy harvesting, quantum computing, structural-integrity monitoring, information storage, and more.

In a newly published paper in Science Advances, a group of researchers led by Andrea Alù, founding director of the Photonics Initiative at the Advanced Science Research Center (ASRC) at The Graduate Center, CUNY, and by Massimo Ruzzene, professor of Aeronautics Engineering at Georgia Tech, have experimentally shown that it is possible to efficiently capture and store a wave intact then guide it towards a specific location.

“Our experiment proves that unconventional forms of excitation open new opportunities to gain control over wave propagation and scattering,” said Alù. “By carefully tailoring the time dependence of the excitation, it is possible to trick the wave to be efficiently stored in a cavity, and then release it on demand towards the desired direction.”

In a study published in Scientific Reports, a group of researchers affiliated with São Paulo State University (UNESP) in Brazil describes an important theoretical finding that may contribute to the development of quantum computing and spintronics (spin electronics), an emerging technology that uses electron spin or angular momentum rather than electron charge to build faster, more efficient devices.

The study was supported by São Paulo Research Foundation—FAPESP. Its principal investigator was Antonio Carlos Seridonio, a professor in UNESP’s Department of Physics and Chemistry at Ilha Solteira, São Paulo State. His graduate students Yuri Marques, Willian Mizobata and Renan Oliveira also participated.

The researchers observed that molecules with the capacity to encode information are produced in systems called Weyl semimetals when time-reversal symmetry is broken.

The proof-of-concept demonstrations herald a major step forward in quantum communications.

You’ve probably heard of Schrödinger’s cat, the unfortunate feline in a box that is simultaneously alive and dead until the box is opened to reveal its actual state. Well, now wrap your mind around Schrödinger’s time, a situation in which one event can simultaneously be the cause and effect of another event.

Then again, maybe not.

In a previous post, I explained why quantum mechanics predicts that there are countless versions of you running around in what could be an infinite number of parallel universes.

This time, I’m going to introduce a controversial proposal by MIT physicist Max Tegmark, that uses these parallel universes to argue that you might actually be immortal.

Gravity was the first fundamental force that humanity recognized, yet it remains the least understood. Physicists can predict the influence of gravity on bowling balls, stars and planets with exquisite accuracy, but no one knows how the force interacts with minute particles, or quanta. The nearly century-long search for a theory of quantum gravity — a description of how the force works for the universe’s smallest pieces — is driven by the simple expectation that one gravitational rulebook should govern all galaxies, quarks and everything in between. [Strange Quarks and Muons, Oh My! Nature’s Tiniest Particles Dissected (Infographic)].

A new high definition radar system that could change the nature of warfare has been demonstrated for the first time. The result, quantum radar, is a high definition detection system that provides a much more detailed image of targets while itself remaining difficult to detect. Quantum radars could provide users with enough detail to identify aircraft, missiles, and other aerial targets by specific model.

According to the MIT Technology Review, researchers at Austria’s Institute of Science and Technology used entangled microwaves to create the world’s first quantum radar system.

Two researchers at Harvard University, Aavishkar A. Patel and Subir Sachdev, have recently presented a new theory of a Planckian metal that could shed light on previously unknown aspects of quantum physics. Their paper, published in Physical Review Letters, introduces a lattice model of fermions that describes a Planckian metal at low temperatures (Tà 0).

Metals contain numerous electrons, which carry electric current. When physicists consider the electrical resistance of metals, they generally perceive it as arising when the flow of current-carrying electrons is interrupted or degraded due to electrons scattering off impurities or off the crystal lattice in the metal.

“This picture, put forth by Drude in 1900, gives an equation for the electrical resistance in terms of how much time electrons spend moving freely between successive collisions,” Patel told Phys.org. “The length of this time interval between collisions, called the ‘relaxation time,’ or ‘electron liftetime,’ is typically long enough in most common metals for the electrons to be defined as distinct, mobile objects to a microscopic observer, and the Drude picture works remarkably well.”

Since their experimental discovery, magnetic skyrmions—tiny magnetic knots—have moved into the focus of research. Scientists from Hamburg and Kiel have now been able to show that individual magnetic skyrmions with a diameter of only a few nanometers can be stabilized in magnetic metal films even without an external magnetic field. They report on their discovery in the journal Nature Communications.

The existence of magnetic skyrmions as particle-like objects was predicted 30 years ago by theoretical physicists, but could only be proven experimentally in 2013. Skyrmions with a diameter from micrometers to a few nanometers were discovered in different magnetic material systems. Although they can be generated on a surface of a few atoms and manipulated with electric currents, they show a high stability against external influences. This makes them potential candidates for future data storage or logic devices. In order to be competitive for technological applications, however, skyrmions must not only be very small, but also stable without an applied magnetic field.

Researchers at the universities of Hamburg and Kiel have now taken an important step in this direction. On the basis of quantum mechanical numerical calculations carried out on the supercomputers of the North-German Supercomputing Alliance (HLRN), the physicists from Kiel were able to predict that individual skyrmions with a diameter of only a few nanometers would appear in an atomically thin, ferromagnetic cobalt film (see Fig. 1). “The stability of the magnetic knots in these films is due to an unusual competition between different magnetic interactions,” says Sebastian Meyer, Ph.D. student in Prof. Stefan Heinze’s research group at the Kiel University.