NIST researchers have developed a “universal quantum bus” that allows quantum information to be transferred between different components of a quantum computer operating at different frequencies. The system uses a non-linear crystal to up-convert low-energy photons to higher frequencies while minimizing noise. This enables quantum circuits to communicate between various materials systems, such as quantum dots, ensembles of atoms, and trapped ions.
The key technical achievement was achieving a world record in detecting the intensity of an ultra-faint light source, comparable to the Hubble Space Telescope but operating 100 times faster and with equivalent accuracy. The researchers used a transition edge sensor (TES) detector cooled to near absolute zero to measure the extremely weak signals. By filtering out background noise and dark counts, they were able to make precise measurements in a fraction of the time previously required.
The up-conversion scheme could eventually become a universal quantum bus, enabling quantum computers to communicate between different components operating at various frequencies. This could lead to more powerful quantum computing systems in the future.
Source: https://www.nist.gov/news-events/news/2017/09/driving-universal-quantum-bus
Keywords: photons, quantum states, superconducting material, optics, quantum bus
