Entanglement generation with a ring resonator
By carefully engineering the geometry of a micrometer-scale, ring-shaped resonator, researchers at NIST produced pairs of entangled photons (particles of light) that have two very different colors or wavelengths. Light from a pump laser (purple) generates one photon in each pair at a visible-light wavelength (red); the other photon has a wavelength in the telecommunications (near-infrared) part of the spectrum (blue). From the perspective of quantum communication, these pairings combine the best of both worlds in an optical circuit: The visible-light partner can interact with trapped atoms, ions, or other systems that serve as quantum versions of computer memory, while the telecommunications wavelength member of each couple is free to propagate over long distances through an optical fiber network.
February 2019 • NIST • https://www.nist.gov/news-events/news/2019/02/entangling-photons-different-colors • Tagged: Illustration, Journal Covers
This illustration was originally created as a cover submission to Nature Physics (in the end, not selected for the cover). Before submitting, I created a mock version to see how it might look, given the typical layout of the Nature Physics journal:
Here is the original concept, showing that the wavelengths of light involved would connect quantum memory to global communications networks:
And an early draft of the ring resonator and photons: