1,598 research outputs found
Saturation of atomic transitions using sub-wavelength diameter tapered optical fibers in rubidium vapor
We experimentally investigate ultralow-power saturation of the rubidium D2
transitions using a tapered optical fiber (TOF) suspended in a warm Rb vapor. A
direct comparison of power-dependent absorption measurements for the TOF system
with those obtained in a standard free-space vapor cell system highlights the
differences in saturation behavior for the two systems. The effects of
hyperfine pumping in the TOF system are found to be minimized due to the short
atomic transit times through the highly confined evanescent optical mode guided
by the TOF. The TOF system data is well-fit by a relatively simple empirical
absorption model that indicates nanoWatt-level saturation powers.Comment: 6 pages, 6 figure
Probabilistic Quantum Encoder for Single-Photon Qubits
We describe an experiment in which a physical qubit represented by the
polarization state of a single-photon was probabilistically encoded in the
logical state of two photons. The experiment relied on linear optics,
post-selection, and three-photon interference effects produced by a parametric
down-conversion photon pair and a weak coherent state. An interesting
consequence of the encoding operation was the ability to observe entangled
three-photon Greenberger-Horne-Zeilinger states.Comment: 4 pages, 4 figures; submitted to Phys. Rev.
Experimental Demonstration of a Quantum Circuit using Linear Optics Gates
One of the main advantages of an optical approach to quantum computing is the
fact that optical fibers can be used to connect the logic and memory devices to
form useful circuits, in analogy with the wires of a conventional computer.
Here we describe an experimental demonstration of a simple quantum circuit of
that kind in which two probabilistic exclusive-OR (XOR) logic gates were
combined to calculate the parity of three input qubits.Comment: v2 is final PRA versio
- …