Category Physics

New Single-Mode Semiconductor Laser delivers Power with Scalability

Schematic of the Berkeley Surface Emitting Laser (BerkSEL)
Schematic of the Berkeley Surface Emitting Laser (BerkSEL) illustrating the pump beam (blue) and the lasing beam (red). The unconventional design of the semiconductor membrane synchronizes all unit-cells (or resonators) in phase so that they are all participating in the lasing mode. (Image courtesy of the Kanté group)

Berkeley engineers have created a new type of semiconductor laser that accomplishes an elusive goal in the field of optics: the ability to maintain a single mode of emitted light while maintaining the ability to scale up in size and power. It is an achievement that means size does not have to come at the expense of coherence, enabling lasers to be more powerful and to cover longer distances for many applications.

A research team led by Boubacar Kanté, Chenming Hu Asso...

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Robot Overcomes Uncertainty to Retrieve Buried Objects

the team of researchers with their project
Caption:Fadel Adib, associate professor in the Department of Electrical Engineering and Computer Science and director of the Signal Kinetics group in the MIT Media Lab (far left) with (from left to right) Tara Boroushaki, Nazish Naeem, and Laura Dodds, research assistants in the Signal Kinetics group.
Credits:Image: James Day, MIT Media Lab

FuseBot is a new robotic system that fuses visual information and radio-frequency signals to efficiently find hidden items buried under a pile of objects, whether or not the targeted item has an RFID tag.

For humans, finding a lost wallet buried under a pile of items is pretty straightforward — we simply remove things from the pile until we find the wallet...

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Is there a Right-handed version of our Left-handed Universe?

From left, ORNL’s Matthew Frost and Leah Broussard used a neutron scattering instrument at the Spallation Neutron Source to search for a dark matter twin to the neutron. Credit: Genevieve Martin/ORNL, U.S. Dept. of Energy

To solve a long-standing puzzle about how long a neutron can “live” outside an atomic nucleus, physicists entertained a wild but testable theory positing the existence of a right-handed version of our left-handed universe. They designed a mind-bending experiment at the Department of Energy’s Oak Ridge National Laboratory to try to detect a particle that has been speculated but not spotted...

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Topological Superconductors: Fertile ground for Elusive Majorana (‘angel’) Particle

Scanning tunnelling microscopy (STM) images: edge of FeSe/STO, with inset atomic-resolution STM showing the topmost Se atom arrangement and crystal orientation

Majorana fermions promise information technology with zero resistance. A new, multi-node FLEET review investigates the search for Majorana fermions in iron-based superconductors.

The elusive Majorana fermion, or ‘angel particle’ proposed by Ettore Majorana in 1937, simultaneously behaves like a particle and an antiparticle — and surprisingly remains stable rather than being self-destructive.

Majorana fermions promise information and communications technology with zero resistance, addressing the rising energy consumption of modern electronics (already 8% of global electricity consumption), and promising a sustainable future...

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