Optics

Optical sensors are used all around the world to monitor the condition of difficult-to-access places like the underbellies of bridges, the exterior walls of tunnels, the feet of dams, long pipelines and railways in remote areas.


Electrical engineering researchers have developed a unique nanoscale device that demonstrates mechanical transportation of light.

The nanoscale device that can capture, measure and transport fundamental particles of light - photons. The tiny device is just 0.7 micrometers by 50 micrometer (about .00007 by .005 centimeters) and works almost like a seesaw. On each side of the "seesaw benches," researchers etched an array of holes, called photonic crystal cavities. These cavities capture photons that streamed from a nearby source. 


Using twisted light to send data at almost unimaginable speeds is not new but researchers have developed a similar technique using radio waves - high speeds without the hassles that go with optical systems. 


The invention of fiber optics revolutionized the way we share information, allowing us to transmit data at volumes and speeds we'd only previously dreamed of, and now are breaking another barrier, designing nano-optical cables small enough to replace the copper wiring on computer chips.

This could result in radical increases in computing speeds and reduced energy use by electronic devices.

"We're already transmitting data from continent to continent using fiber optics, but the killer application is using this inside chips for interconnects—that is the Holy Grail," says Zubin Jacob, an electrical engineering professor leading the research. "What we've done is come up with a fundamentally new way of confining light to the nano scale." 


It’s hard to focus after a bad night’s sleep and by using mice and flashes of light, scientists have found why; just a few nerve cells in the brain may control the switch between internal thoughts and external distractions.

The study  may be a breakthrough in understanding how a critical part of the brain, called the thalamic reticular nucleus (TRN), influences consciousness. 


Physicists investigating tubular biological microstructures that showed unexpected luminescence after heating. Bioinspired peptides, like the ones investigated, could be useful for applications in optical fibers, biolasers and future quantum computers.

The luminous peptide microstructures self-assemble in a water environment. After heating them with a laser, they showed luminescence in the green range of the optical spectrum.

Topological transport of light is the photonic analog of topological electron flow in certain semiconductors.

In the electron case, the current flows around the edge of the material but not through the bulk. It is "topological" in that even if electrons encounter impurities in the material the electrons will continue to flow without losing energy.


We all understand light has a wide electromagnetic spectrum and we only see a small band of that. In physics terms, that is between 400 - 700 nanometers and they show up as colors,from violet to red.

We can't see in the ultraviolet radiation spectrum because it is a shorter wavelength than what we can detect - violet - which is why it's in the name, and we can't see infrared because its wavelength is longer than red, which is why the name is infrared. 


Lasers are ubiquitous but there are still wavelengths for which only large and expensive ones exist, or none at all. Remote sensing and medical applications call for compact laser systems, for example with wavelengths from the near infrared to the Terahertz region and now researchers at the Technische Universitaet Muenchen and the University of Texas Austin have developed a 400 nanometer thick nonlinear mirror that reflects frequency-doubled output using input light intensity as small as that of a laser pointer.


The high power needed to cut or weld using a laser beam creates its own problem: the beam’s energy deforms the mirrors that focus it. When that happens, the beam expands and loses intensity.

A new type of mirror is being presented at the Optatec trade fair in Frankfurt next week - it can deform itself to correct deformation the laser beams it controls.

Lasers are used in manufacturing to cut materials or weld components together. Laser light is focused to a point using various lenses and mirrors obviously, the smaller the focal point and the higher the energy, the more accurately operators can work with the laser.