315 research outputs found
Experimental Bell Inequality Violation with an Atom and a Photon
We report the measurement of a Bell inequality violation with a single atom
and a single photon prepared in a probabilistic entangled state. This is the
first demonstration of such a violation with particles of different species.
The entanglement characterization of this hybrid system may also be useful in
quantum information applications.Comment: 4 pages, 2 figure
Bell inequality violation with two remote atomic qubits
We observe violation of a Bell inequality between the quantum states of two
remote Yb ions separated by a distance of about one meter with the detection
loophole closed. The heralded entanglement of two ions is established via
interference and joint detection of two emitted photons, whose polarization is
entangled with each ion. The entanglement of remote qubits is also
characterized by full quantum state tomography.Comment: 4 pages, 4 figure
Chimeric toxins: Toxic, disulfide-linked conjugate of concanavalin A with fragment A from diphtheria toxin
Quantum Interference of Photon Pairs from Two Trapped Atomic Ions
We collect the fluorescence from two trapped atomic ions, and measure quantum
interference between photons emitted from the ions. The interference of two
photons is a crucial component of schemes to entangle atomic qubits based on a
photonic coupling. The ability to preserve the generated entanglement and to
repeat the experiment with the same ions is necessary to implement entangling
quantum gates between atomic qubits, and allows the implementation of protocols
to efficiently scale to larger numbers of atomic qubits.Comment: 4 pages, 4 figure
Complete methods set for scalable ion trap quantum information processing
Large-scale quantum information processors must be able to transport and
maintain quantum information, and repeatedly perform logical operations. Here
we demonstrate a combination of all the fundamental elements required to
perform scalable quantum computing using qubits stored in the internal states
of trapped atomic ions. We quantify the repeatability of a multi-qubit
operation, observing no loss of performance despite qubit transport over
macroscopic distances. Key to these results is the use of different pairs of
beryllium ion hyperfine states for robust qubit storage, readout and gates, and
simultaneous trapping of magnesium re-cooling ions along with the qubit ions.Comment: 9 pages, 4 figures. Accepted to Science, and thus subject to a press
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Broadband laser cooling of trapped atoms with ultrafast pulses
We demonstrate broadband laser cooling of atomic ions in an rf trap using
ultrafast pulses from a modelocked laser. The temperature of a single ion is
measured by observing the size of a time-averaged image of the ion in the known
harmonic trap potential. While the lowest observed temperature was only about 1
K, this method efficiently cools very hot atoms and can sufficiently localize
trapped atoms to produce near diffraction-limited atomic images
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