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Physicists have demonstrated quantum entanglement in top quarks and their antimatter partners, a discovery made at CERN. This finding extends the behavior of entangled particles to distances beyond the reach of light-speed communication and opens new avenues for exploring quantum mechanics at high energies.

An experiment by a group of physicists led by University of Rochester physics professor Regina Demina has produced a significant result related to quantum entanglement—an effect that Albert Einstein called “spooky action at a distance.”

Entanglement concerns the coordinated behavior of minuscule particles that have interacted but then moved apart. Measuring properties—like position or momentum or spin—of one of the separated pair of particles instantaneously changes the results of the other particle, no matter how far the second particle has drifted from its twin. In effect, the state of one entangled particle, or qubit, is inseparable from the other.

“At this point, the neutrinos go from passive particles—almost bystanders—to major elements that help drive the collapse,” Savage said. “Supernovae are interesting for a variety of reasons, including as sites that produce heavy elements such as gold and iron. If we can better understand neutrinos and their role in the star’s collapse, then we can better determine and predict the rate of events such as a supernova.”

Scientists seldom observe a supernova close-up, but researchers have used classical supercomputers such as ORNL’s Summit to model aspects of the process. Those tools alone wouldn’t be enough to capture the quantum nature of neutrinos.

“These neutrinos are entangled, which means they’re interacting not just with their surroundings and not just with other neutrinos but with themselves,” Savage said.

Building the quantum internet could be significantly simplified by leveraging existing telecommunications technologies and infrastructure. In recent years, researchers have identified defects in silicon—a widely used semiconductor material—that hold the potential for transmitting and storing quantum information across the prevalent telecommunications wavelengths. These silicon defects might just be the prime contenders to host qubits for efficient quantum communications.

Exploring Quantum Defects in Silicon

“It’s still a Wild West out there,” said Evelyn Hu, the Tarr-Coyne Professor of Applied Physics and of Electrical Engineering at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS). “Even though new candidate defects are a promising quantum memory platform, there is often almost nothing known about why certain recipes are used to create them, and how you can rapidly characterize them and their interactions, even in ensembles. And ultimately, how can we fine-tune their behavior so they exhibit identical characteristics? If we are ever to make a technology out of this wide world of possibilities, we must have ways to characterize them better, faster, and more efficiently.”

Sebastian P. Kish1,2, Patrick J. Gleeson2, Angus Walsh2, Ping Koy Lam3,2, and Syed M. Assad3,2

1Data61, CSIRO, Marsfield, NSW, Australia. 2 Centre of Excellence for Quantum Computation and Communication Technology, Department of Quantum Science and Technology, Research School of Physics, The Australian National University, Canberra, ACT, Australia. 3 Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), Singapore, 138,634, Singapore.

Get full text pdfRead on arXiv VanityComment on Fermat’s library.

A research team is studying how light moves through special circuits called optical waveguides, using a concept called topology. They’ve made an important discovery that combines stable light paths with light particle interactions, which could make quantum computers more reliable and lead to new technological advancements.

Scientific innovation often arises as synthesis from seemingly unrelated concepts. For instance, the reciprocity of electricity and magnetism paved the way for Maxwell’s theory of light, which, up until now, is continually being refined and extended with ideas from quantum mechanics.

Similarly, the research group of Professor Alexander Szameit at the Institute of Physics at the University of Rostock explores light evolution in optical waveguide circuits in the presence of topology. This abstract mathematical concept was initially developed to classify solid geometries according to their global properties. Szameit explains: “In topological systems, light only follows the global characteristics of the waveguide system. Local perturbations to the waveguides such as defects, vacancies, and disorder cannot divert its path.”

Our favorite mathematical constant, pi (π), describing the ratio between a circle’s circumference and its diameter, has taken on new meaning.

The new representation was borne out of the twists and turns of string theory, and two mathematicians’ attempts to better describe particle collisions.

“Our efforts, initially, were never to find a way to look at pi,” says Aninda Sinha of the Indian Institute of Science (IISc) who co-authored the new work with fellow IISc mathematician Arnab Priya Saha.

Intel debuts new chip focused on addressing quantum computing’s wiring bottleneck.

Intel’s millikelvin quantum research control chip, code-named Pando Tree, establishes Intel as the first semiconductor manufacturer to demonstrate the distribution of cryogenic silicon spin qubit control electronics…


Sushil Subramanian is a research scientist at Intel where he works on integrated circuits and systems for qubit control in quantum computers. Co-author Stefano Pellerano is a senior principal engineer and lab director of the RF and Mixed-Signal Circuits Lab where he leads the research and development effort on cryogenic electronics for qubit control.

A trio of physicists, two with Uniwersytet Jagielloński in Poland and one with Swinburne University of Technology in Australia, are proposing the use of temporal printed circuit boards made using time crystals as a way to solve error problems on quantum computers. Krzysztof Giergiel, Krzysztof Sacha and Peter Hannaford have written a paper describing their ideas, which is currently available on the arXiv preprint server.