Stretching for thousands of miles beneath oceans, optical fibers now connect every continent except for Antarctica. But although optical fibers are increasingly replacing copper wires, carrying information via photons instead of electrons, today's computer technology still relies on electronic chips. Now, researchers led by engineers at the Caltech are paving the way for the next generation of computer-chip technology: photonic chips.

While many hotel rooms, recording studios, and even some homes are built with materials to help absorb or reflect sound, mechanisms to truly control the direction of sound waves are still in their infancy. However, researchers at the California Institute of Technology (Caltech) have now created the first tunable acoustic diode-a device that allows acoustic information to travel only in one direction, at controllable frequencies.

Zcube Srl, a research venture of the Italian pharmaceutical company Zambon, and Caltech have signed an exclusive research and option agreement to develop and commercialize skin patches that contain embedded carbon nanotubes for delivering drugs.

Artificial intelligence has been the inspiration for countless books and movies, as well as the aspiration of countless scientists and engineers. Researchers at Caltech have now taken a major step toward creating artificial intelligence—not in a robot or a silicon chip, but in a test tube. The researchers are the first to have made an artificial neural network out of DNA, creating a circuit of interacting molecules that can recall memories based on incomplete patterns, just as a brain can.

Environmental scientist and engineer Michael Hoffmann of Caltech has received a $400,000 grant from the Bill & Melinda Gates Foundation to build a solar-powered portable toilet that could help solve a major health problem in developing countries. 

The power output of wind farms can be increased by an order of magnitude—at least tenfold—simply by optimizing the placement of turbines on a given plot of land, say researchers at the California Institute of Technology (Caltech) who have been conducting a unique field study at an experimental two-acre wind farm in northern Los Angeles County. 

When geologists survey an area of land for the potential that gas or petroleum deposits could exist there, they must take into account the composition of rocks that lie below the surface. Previous research had suggested that compaction bands might act as barriers to the flow of oil or gas. Now, researchers led by José Andrade have analyzed X-ray images of Aztec sandstone and revealed that compaction bands are actually more permeable than earlier models indicated.

In many ways, life is like a computer. An organism's genome is the software that tells the cellular and molecular machinery—the hardware—what to do. But instead of electronic circuitry, life relies on biochemical circuitry—complex networks of reactions and pathways that enable organisms to function. Now, researchers at Caltech have built the most complex biochemical circuit ever created from scratch, made with DNA-based devices in a test tube that are analogous to the electronic transistors on a computer chip.

Caltech scientists have concocted a recipe for a thermoelectric material—one that converts heat energy into electricity—that might be able to operate off nothing more than the heat of a car's exhaust. In a paper published in Nature this month, G. Jeffrey Snyder and his colleagues reported on a compound that shows high efficiency in a temperature range of around 260 to 1160 degrees Fahrenheit. In other words, the heat escaping out your car's tailpipe could be used to help power its electrical components.

A team of researchers from the University of California, Los Angeles (UCLA), Caltech, and the University of Louisville have used a stimulating electrode array to assist a paralyzed man to stand, step on a treadmill with assistance, and, over time, to regain voluntary movements of his limbs. The electrical signals provided by the array, the researchers have found, stimulate the spinal cord's own neural network so that it can use the sensory input derived from the legs to direct muscle and joint movements.