Abstract:
The ability to produce entangled particles in controllable manners is essential for any quantum technology. Entanglement between light particles: photons, is particularly crucial for quantum communication due to the light's noninteractive nature and long-lasting coherence. Resources producing entangled multi-photon cluster states will enable communication between remote quantum nodes since the inbuilt redundancy of cluster photons allows repeated local measurements, compensating for losses and probabilistic-Bell measurements. For feasible applications, the cluster generation should be fast, deterministic, and most importantly, its photons - indistinguishable, permitting measurements and clusters fusion by interfering photons. Using periodic excitation of a semiconductor quantum dot confined spin, we demonstrate the first multi-indistinguishable-photon cluster, featuring genuinely infinite length, deterministic, gigahertz generation rate, and optimized entanglement-length of 10 photons. The photons indistinguishability opens new possibilities for scaling up the cluster's dimensionality either by fusion and/or by time-delayed feedback. Our first demonstration exceeds the minimal resource quality requirement for constructing quantum repeaters for quantum communication. Nevertheless, further significant improvements both in entanglement length and photon indistinguishability are feasible, by enhancing the radiative rate using the Purcell effect.
Location: PSC 3150 or Teams (Click here to join the meeting)
For more information, please contact Garnett Bryant, (garnettb@umd.edu)