1,577 research outputs found
Proposal for teleportation of the wave function of a massive particle
We propose a scheme for teleporting an atomic center-of-mass wave function
between distant locations. The scheme uses interactions in cavity quantum
electrodynamics to facilitate a coupling between the motion of an atom trapped
inside a cavity and external propagating light fields. This enables the
distribution of quantum entanglement and the realization of the required
motional Bell-state analysis.Comment: 4 pages, 3 figure
Observation of the Vacuum-Rabi Spectrum for One Trapped Atom
The transmission spectrum for one atom strongly coupled to the field of a
high-finesse optical resonator is observed to exhibit a clearly resolved
vacuum-Rabi splitting characteristic of the normal modes in the eigenvalue
spectrum of the atom-cavity system. A new Raman scheme for cooling atomic
motion along the cavity axis enables a complete spectrum to be recorded for an
individual atom trapped within the cavity mode, in contrast to all previous
measurements in cavity QED that have required averaging over many atoms.Comment: 5 pages with 4 figure
Cavity QED "By The Numbers"
The number of atoms trapped within the mode of an optical cavity is
determined in real time by monitoring the transmission of a weak probe beam.
Continuous observation of atom number is accomplished in the strong coupling
regime of cavity quantum electrodynamics and functions in concert with a
cooling scheme for radial atomic motion. The probe transmission exhibits sudden
steps from one plateau to the next in response to the time evolution of the
intracavity atom number, from N >= 3 to N = 2 to 1 to 0, with some trapping
events lasting over 1 second.Comment: 5 pages, 4 figure
Heralded multiphoton states with coherent spin interactions in waveguide QED
WaveguideQEDoffers the possibility of generating strong coherent atomic
interactions either through appropriate atomic configurations in the
dissipative regime or in the bandgap regime. In this work, we show how to
harness these interactions in order to herald the generation of highly
entangled atomic states, which afterwards can be mapped to generate single mode
multi-photonic states with high fidelities.Weintroduce two protocols for the
preparation of the atomic states, we discuss their performance and compare them
to previous proposals. In particular, we show that one of them reaches high
probability of success for systems with many atoms but low Purcell factors
Nonlinear spectroscopy in the strong-coupling regime of cavity QED
A nonlinear spectroscopic investigation of a strongly coupled atom-cavity system is presented. A two-field pump-probe experiment is employed to study nonlinear structure as the average number of intracavity atoms is varied from N̅≈4.2 to N̅≈0.8. Nonlinear effects are observed for as few as 0.1 intracavity pump photons. A detailed semiclassical simulation of the atomic beam experiment gives reasonable agreement with the data for N̅≳2 atoms. The simulation procedure accounts for fluctuations in atom-field coupling which have important effects on both the linear and nonlinear probe transmission spectra. A discrepancy between the simulations and the experiments is observed for small numbers of atoms (N̅≲1). Unfortunately, it is difficult to determine if this discrepancy is a definitive consequence of the quantum nature of the atom-cavity coupling or a result of the severe technical complications of the experiment
Quantum Spin Dynamics with Pairwise-Tunable, Long-Range Interactions
We present a platform for the simulation of quantum magnetism with full
control of interactions between pairs of spins at arbitrary distances in one-
and two-dimensional lattices. In our scheme, two internal atomic states
represent a pseudo-spin for atoms trapped within a photonic crystal waveguide
(PCW). With the atomic transition frequency aligned inside a band gap of the
PCW, virtual photons mediate coherent spin-spin interactions between lattice
sites. To obtain full control of interaction coefficients at arbitrary
atom-atom separations, ground-state energy shifts are introduced as a function
of distance across the PCW. In conjunction with auxiliary pump fields,
spin-exchange versus atom-atom separation can be engineered with arbitrary
magnitude and phase, and arranged to introduce non-trivial Berry phases in the
spin lattice, thus opening new avenues for realizing novel topological spin
models. We illustrate the broad applicability of our scheme by explicit
construction for several well known spin models.Comment: 18 pages, 10 figure
Reply to the Comment on `Deterministic Single-Photon Source for Distributed Quantum Networking'
Reply to the comment of H. J. Kimble [quant-ph/0210032] on the experiment
realizing a "deterministic single-photon source for distributed quantum
networking" by Kuhn, Hennrich, and Rempe [Phys. Rev. Lett. 89, 067901 (2002),
quant-ph/0204147].Comment: 1 page 1 figur
Quantum state transfer between motion and light
We describe schemes for transferring quantum states between light fields and
the motion of a trapped atom. Coupling between the motion and the light is
achieved via Raman transitions driven by a laser field and the quantized field
of a high-finesse microscopic cavity mode. By cascading two such systems and
tailoring laser field pulses, we show that it is possible to transfer an
arbitrary motional state of one atom to a second atom at a spatially distant
site.Comment: 10 pages, RevTex, 6 figures, to appear in Journal of Optics B:
Quantum and Semiclassical Optic
Deterministic generation of arbitrary photonic states assisted by dissipation
A scheme to utilize atom-like emitters coupled to nanophotonic waveguides is
proposed for the generation of many-body entangled states and for the
reversible mapping of these states of matter to photonic states of an optical
pulse in the waveguide. Our protocol makes use of decoherence-free subspaces
(DFS) for the atomic emitters with coherent evolution within the DFS enforced
by strong dissipative coupling to the waveguide. By switching from subradiant
to superradiant states, entangled atomic states are mapped to photonic states
with high fidelity. An implementation using ultracold atoms coupled to a
photonic crystal waveguide is discussed.Comment: 15 pages, 4 figure
State-Insensitive Cooling and Trapping of Single Atoms in an Optical Cavity
Single Cesium atoms are cooled and trapped inside a small optical cavity by
way of a novel far-off-resonance dipole-force trap (FORT), with observed
lifetimes of 2 to 3 seconds. Trapped atoms are observed continuously via
transmission of a strongly coupled probe beam, with individual events lasting ~
1 s. The loss of successive atoms from the trap N = 3 -> 2 -> 1 -> 0 is thereby
monitored in real time. Trapping, cooling, and interactions with strong
coupling are enabled by the FORT potential, for which the center-of-mass motion
is only weakly dependent on the atom's internal state.Comment: 5 pages, 4 figures Revised version to appear in Phys. Rev. Let
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