



@article {2290,
	title = {Quantum repeaters based on two species trapped ions},
	journal = {New J. Phys. },
	volume = {21},
	year = {2019},
	month = {05/02/2019},
	abstract = {<p>We examine the viability of quantum repeaters based on two-species trapped ion modules for long distance quantum key distribution. Repeater nodes comprised of ion-trap modules of co-trapped ions of distinct species are considered. The species used for communication qubits has excellent optical properties while the other longer lived species serves as a memory qubit in the modules. Each module interacts with the network only via single photons emitted by the communication ions. Coherent Coulomb interaction between ions is utilized to transfer quantum information between the communication and memory ions and to achieve entanglement swapping between two memory ions. We describe simple modular quantum repeater architectures realizable with the ion-trap modules and numerically study the dependence of the quantum key distribution rate on various experimental parameters, including coupling efficiency, gate infidelity, operation time and length of the elementary links. Our analysis suggests crucial improvements necessary in a physical implementation for co-trapped two-species ions to be a competitive platform in long-distance quantum communication.\&nbsp;</p>},
	doi = {https://doi.org/10.1088/1367-2630/ab2a45},
	url = {https://arxiv.org/abs/1811.10723},
	author = {Siddhartha Santra and Sreraman Muralidharan and Martin Lichtman and Liang Jiang and Christopher Monroe and Vladimir S. Malinovsky}
}
@article {2302,
	title = {High Purity Single Photons Entangled with an Atomic Memory},
	year = {2018},
	abstract = {<p>Trapped atomic ions are an ideal candidate for quantum network nodes, with long-lived identical qubit memories that can be locally entangled through their Coulomb interaction and remotely entangled through photonic channels. The integrity of this photonic interface is generally reliant on purity of single photons produced by the quantum memory. Here we demonstrate a single-photon source for quantum networking based on a trapped 138Ba+ ion with a single photon purity of g2(0)=(8.1\&plusmn;2.3)\&times;10\&minus;5 without background subtraction. We further optimize the tradeoff between the photonic generation rate and the memory-photon entanglement fidelity for the case of polarization photonic qubits by tailoring the spatial mode of the collected light.\&nbsp;</p>},
	url = {https://arxiv.org/abs/1812.01749},
	author = {Clayton Crocker and Martin Lichtman and Ksenia Sosnova and Allison Carter and Sophia Scarano and Christopher Monroe}
}
