Continuous-wave-pumped bichromatic dissipative quadratic soliton femtosecond mode-locking
Peer-Reviewed Publication
Updates every hour. Last Updated: 27-Apr-2026 22:16 ET (28-Apr-2026 02:16 GMT/UTC)
Femtosecond nonlinear frequency conversion underpins classical and quantum photonics but typically requires synchronized mode-locked lasers and complex enhancement cavities. We demonstrate a fundamentally different approach by mode-locking nonlinear frequency conversion through dissipative quadratic soliton physics. This paradigm shift extends soliton-based technologies to diverse cavity platforms and previously inaccessible wavelengths, enabling new opportunities in precision metrology, quantum information science, field control, and ultrafast spectroscopy.
A new paper in Remote Sensing is an advancement on a previous study that demonstrated a model that uses generative AI to combine satellite data and physics-based simulations to forecast a wildfire’s path, intensity and growth rate.The original system relied on data from VIIRS, a polar-orbiting satellite that detects heat signatures with relatively high spatial resolution (within a few hundred meters) but revisits the same location only twice a day. The result is precise but intermittent information; a sequence of snapshots separated by long intervals in which the fire continues to evolve. Now, the new paper published in the journal Remote Sensing presents an advancement of the model. The goal is to reduce uncertainty about where and when a fire started, crucial information for predicting its spread.
Imagine ordering a truffle dish in a fancy restaurant, and you might picture pricey gourmet mushrooms from France or Italy. But today, one of the world’s largest producers of some of the most prized truffles, known as Périgord truffles, isn’t in the northern hemisphere at all — it’s Australia. New findings suggest that part of the reason for their bountiful harvests may be because truffle fungi have fewer microbial competitors in Australia's soils compared with Europe’s.
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Restoring both walking and sensation to patients with paraplegia is an ambitious goal—but a team of researchers from the Keck School of Medicine of USC, the University of California, Irvine (UCI) and the California Institute of Technology (Caltech) is now one step closer. With $8 million in funding from the highly competitive National Science Foundation CyberPhysical Systems program, the team is building a fully implantable brain-computer interface (BCI) that allows patients to use their thoughts to control wearable robotic legs, known as a robotic exoskeleton. The system is designed to help patients walk while also restoring the sensation of walking. In the first full test, the BCI was about 92% accurate at both reading step signals from the brain and delivering artificial walking sensation. Existing brain-computer interfaces that restore walking send signals in just one direction, from brain to device. The team’s early proof-of-concept study, done in a patient with epilepsy who had electrodes implanted as part of her medical care, shows it is possible to build a bidirectional, or two-way, system. During the demonstration, the patient sat on her hospital bed with the device by her side (future versions will be small enough to implant inside the body), while one of the researchers wore the robot exoskeleton. When the patient mimed taking a step, the device signaled the exoskeleton, sending the researcher on a walk around the intensive care unit. The system correctly detected brain signals indicating the intent to walk about 92% of the time. The demonstration helped the researchers earn an Investigational Device Exemption from the U.S. Food and Drug Administration, which allows them to test the device in a clinical trial for patients with paraplegia. They aim to implant electrodes for 30 days as a time, using that window to test and refine the system’s capabilities.