Manipulating Single Atoms

Han Xiao, Luojia Wang, Luqi Yuan +1 more

All-optical manipulation of a single-photon quantum transport is of fundamental importance in quantum nanophotonics. Here, a system consisting of a single-mode waveguide coupling with a V-type three-level atom is proposed, where two excited states of the atom are strongly driven by the external coherent field. Transmission and reflection spectra for the output photon at different frequency components, including virtual transitions induced by the ultrastrong driving, are calculated. The interaction between the waveguide photon and the driven atom experiences quantum interferences, which leads to a variety of capabilities for manipulating the single-photon transport in the spectral domain. We perform simulations to demonstrate the possibilities of achieving desired frequency conversions as well as generating different correlated single-photon states by using external drive field at chosen strength. Our work therefore studies the single-photon transport in a strongly driven atom–waveguide system and shows applications for all-optically manipulating the single photon in the field of quantum information processing.

Dustin Stuart

Pin-Ju Tsai, Ya-Fen Hsiao, Ying-Cheng Chen

This paper demonstrates the storage and manipulation of heralded single photons generated from a cavity-enhanced spontaneous parametric down-conversion source in atomic memories based on electromagnetically induced transparency. By varying the intensity of the coupling beam during retrieval process, the authors show that the waveform, bandwidth, and nonclassical correlation of the heralded single photons can be manipulated.

Simon Pleasants

Chuanwei Zhang, S. L. Rolston, S. Das Sarma

We analyze a scheme to manipulate quantum states of neutral atoms at individual sites of optical lattices using focused laser beams. Spatial distributions of focused laser intensities induce position-dependent energy shifts of hyperfine states, which, combined with microwave radiation, allow selective manipulation of quantum states of individual target atoms. We show that various errors in the manipulation process are suppressed below ${10}^{\ensuremath{-}4}$ with properly chosen microwave pulse sequences and laser parameters. A similar idea is also applied to measure quantum states of single atoms in optical lattices.