Precision is key for many kinds of advanced technology and a lack of precision can prevent a technology from being made. For example, quantum computing requires very exact devices because they do not operate with traditional signals, but individual quanta. Researchers at the NIST, University of California, San Diego, and Politecnico di Milano have successfully created the first silicon-based heralded single photon source.
This is a major discovery for quantum computing as the field requires single photon sources, and ones made out of silicon have the advantage of a modern silicon industry capable of fabrication. The device is also able to operate at room temperature and at frequencies used for modern telecommunications. Unfortunately a single photon source is not quite bright enough for what will be needed in quantum computers, but combining them should take care of that.
Other silicon-based optical components have been made recently, including single photon detectors and interferometers, which will be needed for controlling photon entanglement. Ultimately it will be a combination of all of these devices on a single chip that will have practical applications.