57 research outputs found
Coherent control of quantum transport: modulation-enhanced phase detection and band spectroscopy
Amplitude modulation of a tilted optical lattice can be used to steer the
quantum transport of matter wave packets in a very flexible way. This allows
the experimental study of the phase sensitivity in a multimode interferometer
based on delocalization-enhanced Bloch oscillations and to probe the band
structure modified by a constant force.Comment: 8 pages, 3 figures, Submitted to EPJ Special Topics for the special
issue on "Novel Quantum Phases and Mesoscopic Physics in Quantum Gases
Optically loaded Strontium lattice clock with a single multi-wavelength reference cavity
We report on the realization of a new compact strontium optical clock using a
2-D magneto-optical-trap (2D-MOT) as cold atomic source and a multi-wavelength
cavity as the frequency stabilization system. All needed optical frequencies
are stabilized to a zero-thermal expansion high-finesse optical resonator and
can be operated without frequency adjustments for weeks. We present the
complete characterization of the apparatus. Optical control of the atomic
source allows us to perform low-noise clock operation without atomic signal
normalization. Long- and short-term stability tests of the clock have been
performed for the 88 Sr bosonic isotope by means of interleaved clock
operation. Finally, we present the first preliminary accuracy budget of the
system
Generation of a flat-top laser beam for gravitational wave detectors by means of a nonspherical Fabry-Perot resonator
We have tested a new kind of Fabry-Perot long-baseline optical resonator proposed to reduce the thermal noise sensitivity of gravitational wave interferometric detectors--the "mesa beam" cavity--whose flat top beam shape is achieved by means of an aspherical end mirror. We present the fundamental mode intensity pattern for this cavity and its distortion due to surface imperfections and tilt misalignments, and contrast the higher order mode patterns to the Gauss-Laguerre modes of a spherical mirror cavity. We discuss the effects of mirror tilts on cavity alignment and locking and present measurements of the mesa beam tilt sensitivity
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