Miniscule mirrored cavities connect quantum memories

Tiny, nanoscale mirrors were constructed to trap light around atoms inside of diamond crystals, acting like a series of funhouse mirrors. The mirrored cavities in the crystal allow light to bounce back and forth up to 10,000 times, enhancing the normally weak interaction between light and the electronic spin states in the atoms. As a result, a 200-microsecond spin-coherence time – how long the memory encoded in the electron spin state lasts – was produced.

The enhanced interactions between light and atoms and the extended spin-coherence times are essential steps toward realizing real-world quantum memories and, hence, quantum computing systems, which could solve some problems faster than conventional systems. Additionally, these advances could significantly impact the development of high-security, long-distance, cryptographic fiber optic communication networks.