title: Highly reduced fine-structure splitting in InAs/InP quantum dots offering an efficient on-demand entangled 1.55-microm photon emitter.
abstract: To generate entangled photon pairs via quantum dots (QDs), the exciton fine-structure splitting (FSS) must be comparable to the exciton homogeneous linewidth. Yet in the (In,Ga)As/GaAs QD, the intrinsic FSS is about a few tens microeV. To achieve photon entanglement, it is necessary to cherry-pick a sample with extremely small FSS from a large number of samples or to apply a strong in-plane magnetic field. Using theoretical modeling of the fundamental causes of FSS in QDs, we predict that the intrinsic FSS of InAs/InP QDs is an order of magnitude smaller than that of InAs/GaAs dots, and, better yet, their excitonic gap matches the 1.55 microm fiber optic wavelength and, therefore, offers efficient on-demand entangled photon emitters for long distance quantum communication.
authors.affiliation: Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, 230026, People's Republic of China. helx@ustc.edu.cn
authors.forename: Lixin
authors.initials: L
authors.lastname: He
authors.forename: Ming
authors.initials: M
authors.lastname: Gong
authors.forename: Chuan-Feng
authors.initials: CF
authors.lastname: Li
authors.forename: Guang-Can
authors.initials: GC
authors.lastname: Guo
authors.forename: Alex
authors.initials: A
authors.lastname: Zunger