A solid state source of photon triplets based on quantum dot molecules

• DOI: 10.1038/ncomms15716
• Publication Date: 2017-06-12T09:56:54Z
• Authors: Milad Khoshnegar; Tobias Huber; Ana Predojević; Dan Dalacu; Maximilian Prilmü...; Jean Lapointe; Xiaohua Wu; Philippe Tamarat; Brahim Lounis; Philip Poole; Gregor Weihs; Hamed Majedi
• Keywords: 0301 basic medicine; Quantum Physics; 0303 health sciences; Condensed Matter - Mesoscale and Nanoscale Physics; Science; Q; FOS: Physical sciences; quantum dots; 01 natural sciences; 7. Clean energy; Article; 03 medical and health sciences; quantum information; Mesoscale and Nanoscale Physics (cond-mat.mes-hall); 0103 physical sciences; Quantum Physics (quant-ph); Physics - Optics; Optics (physics.optics)

AbstractProducing advanced quantum states of light is a priority in quantum information technologies. In this context, experimental realizations of multipartite photon states would enable improved tests of the foundations of quantum mechanics as well as implementations of complex quantum optical networks and protocols. It is favourable to directly generate these states using solid state systems, for simpler handling and the promise of reversible transfer of quantum information between stationary and flying qubits. Here we use the ground states of two optically active coupled quantum dots to directly produce photon triplets. The formation of a triexciton in these ground states leads to a triple cascade recombination and sequential emission of three photons with strong correlations. We record 65.62 photon triplets per minute under continuous-wave pumping, surpassing rates of earlier reported sources. Our structure and data pave the way towards implementing multipartite photon entanglement and multi-qubit readout schemes in solid state devices.