news aggregator

Researchers in China have created synthetic magnetic fields within silicon photonic crystals, allowing them to steer and control light on a chip with unprecedented precision. "Beyond immediate applications, the work opens new avenues for studying quantum-inspired phenomena with light," reports Phys.org. "The ability to impose artificial gauge fields in photonic systems could enable devices for optical computing, quantum information, and advanced communication technologies." Slashdot reader alternative_right shares an excerpt from the report: The team achieved this by systematically altering the symmetry of tiny repeating units in silicon photonic crystals. Adjusting the degree of local asymmetry at each point allowed them to 'design' pseudomagnetic fields with tailored spatial patterns, without breaking fundamental time-reversal symmetry. Both theoretical analysis and experiments confirmed that these engineered fields can guide and manipulate light in versatile ways. To demonstrate practical applications, the researchers built two devices commonly used in integrated optics. One was a compact S-shaped waveguide bend that transmitted light with less than 1.83 decibels of signal loss. The other was a power splitter that divided light into two equal paths with low excess loss and minimal imbalance. In a final test, the devices successfully transmitted a high-speed data stream at 140 gigabits per second using a standard telecommunications modulation format, showing that the technique is compatible with existing optical communication systems. The research has been published in Advanced Photonics.

Read more of this story at Slashdot.

An anonymous reader quotes a report from The Intercept: The company behind the Proton Mail email service, Proton, describes itself as a "neutral and safe haven for your personal data, committed to defending your freedom." But last month, Proton disabled email accounts belonging to journalists reporting on security breaches of various South Korean government computer systems following a complaint by an unspecified cybersecurity agency. After a public outcry, and multiple weeks, the journalists' accounts were eventually reinstated -- but the reporters and editors involved still want answers on how and why Proton decided to shut down the accounts in the first place. Martin Shelton, deputy director of digital security at the Freedom of the Press Foundation, highlighted that numerous newsrooms use Proton's services as alternatives to something like Gmail "specifically to avoid situations like this," pointing out that "While it's good to see that Proton is reconsidering account suspensions, journalists are among the users who need these and similar tools most." Newsrooms like The Intercept, the Boston Globe, and the Tampa Bay Times all rely on Proton Mail for emailed tip submissions. Shelton noted that perhaps Proton should "prioritize responding to journalists about account suspensions privately, rather than when they go viral." On Reddit, Proton's official account stated that "Proton did not knowingly block journalists' email accounts" and that the "situation has unfortunately been blown out of proportion." The two journalists whose accounts were disabled were working on an article published in the August issue of the long-running hacker zine Phrack. The story described how a sophisticated hacking operation -- what's known in cybersecurity parlance as an APT, or advanced persistent threat -- had wormed its way into a number of South Korean computer networks, including those of the Ministry of Foreign Affairs and the military Defense Counterintelligence Command, or DCC. The journalists, who published their story under the names Saber and cyb0rg, describe the hack as being consistent with the work of Kimsuky, a notorious North Korean state-backed APT sanctioned by the U.S. Treasury Department in 2023. As they pieced the story together, emails viewed by The Intercept show that the authors followed cybersecurity best practices and conducted what's known as responsible disclosure: notifying affected parties that a vulnerability has been discovered in their systems prior to publicizing the incident. Phrack said the account suspensions created a "real impact to the author. The author was unable to answer media requests about the article." Phrack noted that the co-authors were already working with affected South Korean organizations on responsible disclosure and system fixes. "All this was denied and ruined by Proton," Phrack stated. Phrack editors said that the incident leaves them "concerned what this means to other whistleblowers or journalists. The community needs assurance that Proton does not disable accounts unless Proton has a court order or the crime (or ToS violation) is apparent."

Read more of this story at Slashdot.