False-color scanning electron micrograph of a nanophotonic frequency converter containing a ring resonator (blue shaded part), and a waveguide (red part) is used to inject light into the ring resonator. The input signal is represented by a purple arrow and converted to a new frequency (blue arrow) by using two pump laser pointer (bright red and dark red arrows).
Converting a single photon from one color or frequency to another color or frequency is an important tool in quantum communication. It uses the subtle relationship between the subatomic properties of photons (particles of light) to safely store and transmit information. Scientists at the National Institute of Standards and Technology have now developed a miniaturized frequency converter using technology similar to that of manufacturing computer chips.
This tiny device will help to improve security and increase the working distance of the next-generation quantum communication system. It can be adjusted to make it suitable for a variety of purposes, and it is also easy to integrate with other information processing components, and Can be mass-produced.
This new nanoscale optical frequency converter effectively converts photons from one frequency to another while consuming only a small amount of power and adding a very low noise level, that is, the background light is not correlated with the input signal.
The frequency converter is the key to solving two green laser pointer problems. The optimal frequency for generating and storing information in a quantum system is usually much higher than the frequency required to transmit this information over a distance of more than kilometer in an optical fiber. Converting photons between these frequencies requires a frequency shift of several hundred terahertz (one terahertz equals one trillion wave cycles per second).