27,901 research outputs found
Detector Description and Performance for the First Coincidence Observations between LIGO and GEO
For 17 days in August and September 2002, the LIGO and GEO interferometer
gravitational wave detectors were operated in coincidence to produce their
first data for scientific analysis. Although the detectors were still far from
their design sensitivity levels, the data can be used to place better upper
limits on the flux of gravitational waves incident on the earth than previous
direct measurements. This paper describes the instruments and the data in some
detail, as a companion to analysis papers based on the first data.Comment: 41 pages, 9 figures 17 Sept 03: author list amended, minor editorial
change
Coherent coupling between radio frequency, optical, and acoustic waves in piezo-optomechanical circuits
The interaction of optical and mechanical modes in nanoscale optomechanical
systems has been widely studied for applications ranging from sensing to
quantum information science. Here, we develop a platform for cavity
optomechanical circuits in which localized and interacting 1550 nm photons and
2.4 GHz phonons are combined with photonic and phononic waveguides. Working in
GaAs facilitates manipulation of the localized mechanical mode either with a
radio frequency field through the piezo-electric effect, or optically through
the strong photoelastic effect. We use this to demonstrate a novel acoustic
wave interference effect, analogous to coherent population trapping in atomic
systems, in which the coherent mechanical motion induced by the electrical
drive can be completely cancelled out by the optically-driven motion. The
ability to manipulate cavity optomechanical systems with equal facility through
either photonic or phononic channels enables new device and system
architectures for signal transduction between the optical, electrical, and
mechanical domains
Electrically packaged silicon-organic hybrid (SOH) I/Q-modulator for 64 GBd operation
Silicon-organic hybrid (SOH) electro-optic (EO) modulators combine small
footprint with low operating voltage and hence low power dissipation, thus
lending themselves to on-chip integration of large-scale device arrays. Here we
demonstrate an electrical packaging concept that enables high-density
radio-frequency (RF) interfaces between on-chip SOH devices and external
circuits. The concept combines high-resolution
printed-circuit boards with technically simple metal wire bonds and is amenable
to packaging of device arrays with small on-chip bond pad pitches. In a set of
experiments, we characterize the performance of the underlying RF building
blocks and we demonstrate the viability of the overall concept by generation of
high-speed optical communication signals. Achieving line rates (symbols rates)
of 128 Gbit/s (64 GBd) using quadrature-phase-shiftkeying (QPSK) modulation and
of 160 Gbit/s (40 GBd) using 16-state quadrature-amplitudemodulation (16QAM),
we believe that our demonstration represents an important step in bringing SOH
modulators from proof-of-concept experiments to deployment in commercial
environments
Frequency tuning of a triply-resonant whispering-gallery mode resonator to MHz wide transitions for proposed quantum repeater schemes
Quantum repeaters rely on an interfacing of flying qubits with quantum
memories. The most common implementations include a narrowband single photon
matched in bandwidth and central frequency to an atomic system. Previously, we
demonstrated the compatibility of our versatile source of heralded single
photons, which is based on parametric down-conversion in a triply-resonant
whispering-gallery mode resonator, with alkaline transitions [Schunk et al.,
Optica 2, 773 (2015)]. In this paper, we analyze our source in terms of phase
matching, available wavelength-tuning mechanisms, and applications to
narrow-band atomic systems. We resonantly address the D1 transitions of cesium
and rubidium with this optical parametric oscillator pumped above its
oscillation threshold. Below threshold, the efficient coupling of single
photons to atomic transitions heralded by single telecom-band photons is
demonstrated. Finally, we present an accurate analytical description of our
observations. Providing the demonstrated flexibility in connecting various
atomic transitions with telecom wavelengths, we show a promising approach to
realize an essential building block for quantum repeaters.Comment: 18 pages, 14 figure
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