Frequency comb tagged posts

Time is vital to the functioning of our everyday lives: from the watches on our wrists to the GPS systems in our phones. Communication systems, power grids, and financial transactions all rely on precision timing. Seconds are the vital units of measurement in timekeeping.

Surprisingly, there is still debate over the definition of the second. But recent advances in the world’s most accurate forms of timekeeping may have just changed the game.

Accurate timekeeping has always been part of humankind’s social evolution...

New device creates entangled photons that span the traditional telecommunications spectrum, making it appealing for multi-channel quantum communication and more powerful quantum computers. Credit: Michael Kues, Institut National de la Recherche Scientifique (INRS), University of Quebec, Canada

Discovery is a significant step toward multi-channel quantum communication and higher capacity quantum computers. An international team has built a chip that generates multiple frequencies from a robust quantum system that produces time-bin entangled photons. In contrast to other quantum state realizations, entangled photons don’t need bulky equipment to keep them in their quantum state, and they can transmit quantum information across long distances...

. On-chip visible-to-infrared supercontinuum generation with more than 495 THz spectral bandwidth Credit: http://dx.doi.org/10.1364/OE.23.019596

Sending information with the help of light is an exciting prospect for future technologies. It requires ‘light chips’, made of a special glass (already known for their extremely low losses) which now have been equipped with ‘active’ functionalities, eg generating, strengthening, and modulating light. Their chip is capable of creating a very wide light spectrum that runs from blue to infrared, 470 to 2130 nm wavelengths. By doing so they have made a light chip with the largest frequency range ever.

The width and regularity of the light spectrum plays a central role in fiber optics info transfer...