Proven With Electromagnetic Waves

Scientists at the University of Southampton have experimentally proven the Zel’dovich effect by amplifying electromagnetic waves using a spinning metal cylinder, confirming a theoretical prediction from the 1970s and opening new avenues in technology and quantum physics. Credit: SciTechDaily.com

University of Southampton researchers have confirmed the Zel’dovich effect, where twisted waves are amplified by a rotating object. This finding, previously only demonstrated with sound waves, now applies to electromagnetic waves, with promising implications for quantum physics and energy-efficient technologies.


Physicists at the University of Southampton have successfully tested and confirmed a 50-year-old theory for the first time using electromagnetic waves.

Their experiments demonstrated that the energy of waves can be amplified by bouncing ‘twisted waves’—waves with angular momentum—off a rotating object under specific conditions.


This is known as the ‘Zel’dovich effect’, named after Soviet physicist Yakov Zel’dovich who developed a theory based on this idea in the 1970s. Until now, it was believed to be unobservable with electromagnetic fields.     READ MORE...

Quantum Memory Stores Information

Researchers at University of Oxford have recently created a quantum memory within a trapped-ion quantum network node. Their unique memory design, introduced in a paper in Physical Review Letters, has been found to be extremely robust, meaning that it could store information for long periods of time despite ongoing network activity.

"We are building a network of quantum computers, which use trapped ions to store and process quantum information," Peter Drmota, one of the researchers who carried out the study, told Phys.org. "To connect quantum processing devices, we use single photons emitted from a single atomic ion and utilize quantum entanglement between this ion and the photons."

Trapped ions, charged atomic particles that are confined in space using electromagnetic fields, are a commonly used platform for realizing quantum computations. Photons (i.e., the particles of light), on the other hand, are generally used to transmit quantum information between distant nodes. Drmota and his colleagues have been exploring the possibility of combining trapped ions with photons, to create more powerful quantum technologies.

"Until now, we have implemented a reliable way of interfacing strontium ions and photons, and used this to generate high-quality remote entanglement between two distant network nodes," Drmota said. "On the other hand, high-fidelity quantum logic and long-lasting memories have been developed for calcium ions. In this experiment, we combine these capabilities for the first time, and show that it is possible to create high-quality entanglement between a strontium ion and a photon and thereafter store this entanglement in a nearby calcium ion."

Integrating a quantum memory into a network node is a challenging task, as the criteria that need to be fulfilled for such a system to work are higher than those required for the creation of a standalone quantum processor. Most notably, the developed memory would need to be robust against concurrent network activity.   READ MORE...