Category Physics

Kerry Vahala and collaborators from UC Santa Barbara have found a unique solution to an optics problem. When we last checked in with Caltech’s Kerry Vahala three years ago, his lab had recently reported the development of a new optical device called a turnkey frequency microcomb that has applications in digital communications, precision time keeping, spectroscopy, and even astronomy.

This device, fabricated on a silicon wafer, takes input laser light of one frequency and converts it into an evenly spaced set of many distinct frequencies that form a train of pulses whose length can be as short as 100 femtoseconds (quadrillionths of a second). (The comb in the name comes from the frequencies being spaced like the teeth of a hair comb.)

Now Vahala (BS ’80, MS ’81,...

Physicists at RIKEN have developed an electronic device that hosts unusual states of matter, which could one day be useful for quantum computation.

When a material exists as an ultrathin layer—a mere one or a few atoms thick—it has totally different properties from thicker samples of the same material. That’s because confining electrons to a 2D plane gives rise to exotic states...

If you want to improve the output of solar energy systems, why not also run them at night? That’s the question researchers in Qatar and Jordan addressed as they successfully devised a system that promises to more than double energy output of current solar power stations.

By combining two concepts—a solar updraft system and a cooling downdraft structure—researchers designed a model that could generate 753 MWh of energy annually. That’s enough to power roughly 753 homes for about five weeks or 1,500 60-watt light bulbs nonstop for a year.

The origins of the system, referred to as Solar Tower Power Plant, go back to 1982 when Spanish engineers constructed a chimney-like tower with a mechanical turbine at its base...

While Santa Claus may have a magical sleigh and nine plucky reindeer to help him deliver presents, for companies like FedEx, the optimization problem of efficiently routing holiday packages is so complicated that they often employ specialized software to find a solution.

This software, called a mixed-integer linear programming (MILP) solver, splits a massive optimization problem into smaller pieces and uses generic algorithms to try and find the best solution. However, the solver could take hours—or even days—to arrive at a solution...