Phys.org November 5, 2020
A central research object is the interface between local quantum devices and light quanta that enable the remote transmission of highly sensitive quantum information. Researchers in Germany integrated a thin crystal of erbium-doped yttrium orthosilicate a cryogenic Fabry-Perot resonator leading to 56-fold enhancement of the emission rate with an out-coupling efficiency of 46%. They demonstrated that the emitter properties are not degraded. They observed ensemble-averaged optical coherence up to 0.54 ms, which exceeds the 0.19 ms lifetime of dopants at the cavity field maximum. The approach is also applicable to other solid-state quantum emitters, such as color centers in diamond, and enables coherent and efficient nodes for long-distance quantum networks. The technology can be integrated into existing fiber optic networks…read more. Open Access TECHNICAL ARTICLEÂ
The Garching quantum modem: The crystal disk with the quantum bits of erbium atoms (arrows) is in the middle, the back and forth reflected infrared light is indicated by the red disks. Credit: Christoph Hohmann (MCQST)