Category Physics

A phonon laser formed by coupled optical resonators. Mechanical vibrations in resonator (blue) could be enhanced when the frequency difference of two optical supermodes matches with the frequency mechanical vibrations.
Credit: Micro/Nano Photonics Lab

New laser uses light to create sound. A team of international researchers led by engineers at Washington University in St. Louis has seen the light and now has a lasing system that produces “good vibrations.” They developed a lasing system already adept at producing tiny light packets called photons into a tunable system that also makes little bits of mechanical energy called phonons – the energy products of oscillation, or vibration...

A film deflects from a magnetic field when exposed to light.
Credit: SilkLab, Tufts University

Elastomeric composites can flex, grip, release, or rotate when exposed to lasers, diffuse light or sunlight. Researchers at Tufts University School of Engineering have developed magnetic elastomeric composites that move in different ways when exposed to light, raising the possibility that these materials could enable a wide range of products that perform simple to complex movements, from tiny engines and valves to solar arrays that bend toward the sunlight. The research is described in an article published today in the Proceedings of the National Academy of Sciences.

In biology, there are many examples where light induces movement or change – think of flowers and leaves turning toward sunlight...

EPFL researchers have developed a transistor based on excitons – a type of particle most people have not heard of – that is able to function at room temperature. This breakthrough could lead to a new breed of faster, more energy efficient and smaller electronics.

Excitons could revolutionize the way engineers approach electronics. A team of EPFL researchers has created a new type of transistor – one of the components of circuits – using these particles instead of electrons. What is remarkable is that their exciton-based transistor functions effectively at room temperature, a hitherto insurmountable obstacle. They achieved this by using two 2D materials as semiconductors...

The photo shows a rare-earth crystal that serves as quantum memory. The crystal is cooled to 3 degrees above absolute zero temperature.
Credit: © UNIGE

Quantum communication and cryptography are the future of high-security communication. But many challenges lie ahead before a worldwide quantum network can be set up, including propagating the quantum signal over long distances. One of the major challenges is to create memories with the capacity to store quantum information carried by light. Researchers at the University of Geneva (UNIGE), Switzerland, in partnership with CNRS, France, have discovered a new material in which an element, ytterbium, can store and protect the fragile quantum information even while operating at high frequencies...