Phys.org November 28, 2022
Because of their long coherence times and efficient optical interface, color centers in diamond are promising candidates for quantum memory nodes. Researchers at Harvard University integrated two-qubit network node based on silicon-vacancy centers (SiVs) in diamond nanophotonic cavities. The qubit register consisted of the SiV electron spin acting as a communication qubit and the strongly coupled silicon-29 nuclear spin acting as a memory qubit with a quantum memory time exceeding 2 seconds. They demonstrated electron-photon entangling gates at temperatures up to 1.5 kelvin and nucleus-photon entangling gates up to 4.3 kelvin and efficient error detection in nuclear spin–photon gates by using the electron spin as a flag qubit. According to the researchers this platform is a promising candidate for scalable quantum repeaters… read more. TECHNICAL ARTICLEÂ
A scanning electron microscope image of an array of nanophotonic quantum memories on a diamond chip… Credit: Stas et al.