(Press-News.org) Imagine the benefits if the entire internet got a game-changing upgrade to speed and security. This is the promise of the quantum internet - an advanced system that uses single photons (particles of light) to operate. Researchers at Tohoku University developed a new photonic router that can direct single and (quantum) entangled photons with unprecedented levels of efficiency. This advancement in quantum optics brings us closer to quantum networks and next-generation photonic quantum technologies becoming an everyday reality.
The findings were published in Advanced Quantum Technologies on September 2, 2025.
Photons are the backbone of many emerging quantum applications, from secure communication to powerful quantum computers. To make these technologies practical, photons must be routed quickly and reliably, without disturbing the delicate quantum states they carry. Polarization, the orientation of a photon's electric field, is one of the most common ways to encode quantum information. However, until now, no device had been able to route photons of arbitrary polarization at telecom wavelengths with both low loss and high fidelity.
The research team led by Professor Fumihiro Kaneda from the Graduate School of Science at Tohoku University has overcome this challenge by developing a novel electro-optic router. This router features a compact, specially designed interferometer where the optical paths form a parallelogram instead of a typical rectangle. This design allows for polarization-maintaining operation of all optical components at a nearly normal angle of incidence.
"It shouldn't be like a game of broken telephone where information gets lost along the way," explains Kaneda. "Essentially, our design makes it so that the signal received is as close as possible to the signal that was sent - photon polarization was preserved with over 99% fidelity."
These advancements resulted in a router with a minimal number of optical components, significantly reducing optical loss and enabling stable, high-quality performance.
"It transmits photons with only 0.06 dB of loss, which is only about 1.3%," explains Kaneda, "Not only is it running efficiently at nanosecond speeds, it is already compatible with the telecommunication networks we use today for the internet. The findings from this research provide a valuable foundation for the development of practical quantum network technologies."
In a world-first demonstration, the team also successfully routed two-photon entangled statesーa crucial resource for quantum sensing and quantum networksーwhile maintaining interference visibility of about 97%. This shows that the router can handle not only individual quantum bits, but also complex multiphoton entanglementーa key requirement for scaling up quantum technologies.
Compared with previous approaches, which often suffered from high loss, noise, or distortion, this new device combines all the critical features needed for practical use: low loss, high speed, noise-free operation, and compatibility with existing telecom fiber networks.
END
Routing photonic entanglement towards a quantum internet
2025-09-25
ELSE PRESS RELEASES FROM THIS DATE:
High-pressure processing alters stability of anthocyanin–catechin complexes
2025-09-25
Researchers found that while HPP promotes the formation of anthocyanin–catechin complexes, it simultaneously reduces their thermal and light stability by decreasing the proportion of dominant conformations.
Anthocyanins are natural pigments abundant in fruits, vegetables, tea, and wine, prized for their vivid colors and health benefits including antioxidant, anti-inflammatory, and cardioprotective properties. Yet their poor stability under heat and light has long hindered food applications. Copigmentation—complex formation between anthocyanins and polyphenols such as catechins—enhances both stability ...
Scientists develop a virus cocktail to combat superbugs
2025-09-25
In a major advance for infectious disease treatment, researchers from Monash University and The Alfred have developed a bespoke phage therapy product that uses bacterial viruses, known as ‘bacteriophages’, to combat a highly problematic, antimicrobial resistant bacteria.
The treatment, named Entelli-02, is a five-phage cocktail designed specifically to target Enterobacter cloacae complex (ECC), a group of bacteria responsible for severe, often difficult-to-treat infections.
The study, published in Nature Microbiology, was led by Professor Jeremy J. Barr from the Monash ...
Fishy forensics improves tracking of fish migrations
2025-09-25
As the world’s oceans warm, tropical fish species are moving into cooler waters and exploring new habitats beyond their traditional ranges. Researchers have discovered a new way to track their migration patterns by combining environmental DNA with visual surveys.
“Climate change has already caused more than 12,000 species to shift their homes across land, freshwater and the sea,” says the University of Adelaide’s Dr Chloe Hayes, who has published a study on the new approach.
“In ...
INSEAD launches Master in Finance: a global launchpad for the next generation of financial leaders
2025-09-25
INSEAD, The Business School for the World, today announced the launch of its new Master in Finance (MIF), an innovative pre-experience degree for recent graduates and young professionals.
Designed to meet the growing demand for finance professionals who combine technical mastery with cross-cultural agility, global business acumen, and leadership skills, the INSEAD MIF reflects both market demand and INSEAD’s DNA in leadership education. This pre-experience programme aims to shape the financial leaders of tomorrow.
Shaping Leaders for a Transforming Financial World
Building on the success of INSEAD’s Master in Management ...
Reversing age-related vision decline
2025-09-25
Changes in vision are often a common sign of aging. If you sit in a dimly lit restaurant with anyone over the age of 60, you’ll likely hear the person say, “Hold on — let me pull out my cell phone. I need more light to read the menu!” But what if we could reverse age-related visual decline?
In a new study, UC Irvine researchers explore a possible therapy for addressing “aging” in the eye and for preventing diseases such as age-related macular degeneration (AMD).
“We show the potential for reversing age-related vision loss,” says Dorota Skowronska-Krawczyk, PhD, an associate ...
Crnic Institute breakthrough maps how Down Syndrome biology changes with age
2025-09-25
AURORA, Colo. (Sept. 24, 2025) – In a groundbreaking new study published in Nature Communications, researchers from the Linda Crnic Institute for Down Syndrome (Crnic Institute) at the University of Colorado Anschutz discovered important differences in the physiological changes observed in over 300 individuals with Down syndrome across the lifespan.
The study is part of the ongoing Human Trisome Project, a large, detailed cohort study of people with Down syndrome, including deep annotation ...
Grazing, soil, and biochar: U.S.-China scientists uncover a carbon-boosting superpower in karst lands
2025-09-25
The Grazing Challenge
Pastures feed the world. But grazing animals? They can disturb the soil, speed up carbon loss, and weaken long-term fertility—especially in vulnerable karst soils. With climate change intensifying, scientists are racing to find ways to keep carbon in the ground, not in the air.
Enter: biochar. Think of it as “soil probiotics”—a charcoal-like substance made from organic waste that supercharges soil life and locks away carbon for decades, even centuries.
The Biochar Breakthrough
In a series of clever lab experiments using tall fescue (Festuca arundinacea) and simulated grazing, the team ...
Wilkes Center awards $250,000 Climate Launch Prize to Build up Nepal
2025-09-25
When: Wednesday, September 24, 2025
7:00 p.m. US Eastern Time—Reception
7:30 p.m. US Eastern Time—Announcement
What: The Wilkes Center for Climate Science & Policy at the ...
Biochar boost: Smart monitoring shows sustainable growth for basil
2025-09-25
Geelong, Australia — A team of researchers has discovered that adding biochar to potting mix can significantly improve basil growth while also advancing sustainable farming practices. Using Internet of Things (IoT) technology to track plant health in real time, the study highlights how small changes in growth media can benefit both agriculture and the environment.
The research, published in Biochar, tested six different growth media for basil cultivation over 30 days in “smart growth cabinets.” These controlled chambers allowed ...
Rivers’ hidden helpers: microbes that clean up nitrogen pollution across China
2025-09-25
A new study has revealed how tiny microbes in rivers and wetlands across China help clean up excess nitrogen pollution, offering fresh insights into the health of freshwater ecosystems and the global nitrogen cycle.
Nitrogen is essential for life, but too much of it—often from fertilizer use, fossil fuel burning, and agriculture—ends up in rivers and lakes. This overload can trigger harmful algal blooms, oxygen loss, fish die-offs, and long-term damage to ecosystems. Scientists have long known that microbes play a critical ...