Schematic of a quantum network .
|Quantum networks are
composed of quantum nodes that interact coherently through
quantum channels . For example, a quantum network can
Picture of the two first nodes of
our elementary quantum network.
Photo by Nara Cavalcanti
collective effects of atomic ensembles provide another
means to control the light-matter interface.
Our interest is to develop the physical resources that enable quantum repeaters, thereby allowing entanglement-based quantum communication tasks over quantum networks on distance scales much larger than set by the attenuation length of optical fibers, including quantum cryptography or quantum teleportation.
We worked with ensembles (1, 2 and even 4) of cooled cesium atoms in magneto-optical traps. Non-classically correlated photon pairs with a programmable delay interval have been first generated and, additionally, used as a source of conditional single photons. For more information, please visit our previous homepage.
| "Entanglement of spin waves among four
K. S. Choi, A. Goban, S. B. Papp, S. J. van Enk, and H. J. Kimble, Nature 468, 412-416 (2010)
Caltech Press Release
The quadripartite atomic entanglement is generated for four collective atomic modes of the four ensembles. Images result from background-subtracted fluorescence of the four atomic ensembles .
recently, we demonstrated measurement-induced
entanglement stored in four atomic memories;
user-controlled, coherent transfer of the atomic
entanglement to four photonic channels; and
characterization of the full quadripartite entanglement
using quantum uncertainty relations .
Click here to view the movie of the 3D rendering of the entanglement parameters for the dissipative dynamics of atomic entanglement.
 "A state-insensitive, compensated
C. Lacroûte, K. S. Choi, A. Goban, D. J. Alton, D. Ding, N. P. Stern and H. J. Kimble, New J. Phys. 14 (2012) 023056.
 "Demonstration of a state-insensitive, compensated nanofiber trap"
Simulation of Trapping Potential [3,4].
|To go beyond four
ensembles, we hope to explore a system for more scalable
interface. The fiber-trapped atom array becomes
a natural candidate.
Most recently, we have experimentally realized an optical trap that localizes single Cs atoms ~215 nm from surface of a dielectric nanofiber [3,4].