Scientists have achieved a major advance in developing a single-photon light source, bringing quantum applications such as quantum computing and quantum cryptography closer to reality.

A UCSB research team has created a robust micron-sized semiconductor device that can emit single photons on demand at a rate of 31 million photons per second (31 MHz) into an optical fiber, five times better than previously possible. The single-photon source is based on a semiconductor quantum dot that is structurally robust and provides record-high light extraction efficiencies up to 38 percent.