6,674 research outputs found
Efficient sympathetic motional ground-state cooling of a molecular ion
Cold molecular ions are promising candidates in various fields ranging from
precision spectroscopy and test of fundamental physics to ultra-cold chemistry.
Control of internal and external degrees of freedom is a prerequisite for many
of these applications. Motional ground state cooling represents the starting
point for quantum logic-assisted internal state preparation, detection, and
spectroscopy protocols. Robust and fast cooling is crucial to maximize the
fraction of time available for the actual experiment. We optimize the cooling
rate of ground state cooling schemes for single ions and
sympathetic ground state cooling of . In particular, we
show that robust cooling is achieved by combining pulsed Raman sideband cooling
with continuous quench cooling. Furthermore, we experimentally demonstrate an
efficient strategy for ground state cooling outside the Lamb-Dicke regime.Comment: 11 pages, 11 figure
Detection of motional ground state population of a trapped ion using delayed pulses
Efficient preparation and detection of the motional state of trapped ions is
important in many experiments ranging from quantum computation to precision
spectroscopy. We investigate the stimulated Raman adiabatic passage (STIRAP)
technique for the manipulation of motional states in a trapped ion system. The
presented technique uses a Raman coupling between two hyperfine ground states
in Mg, implemented with delayed pulses, which removes a single
phonon independent of the initial motional state. We show that for a thermal
state the STIRAP population transfer is more efficient than a stimulated Raman
Rabi pulse on a motional sideband. In contrast to previous implementations, a
large detuning of more than 200 times the natural linewidth of the transition
is used. This approach renders STIRAP suitable for atoms in which resonant
laser fields would populate fluorescing excited states and thus impede the
STIRAP process. We use the technique to measure the wavefunction overlap of
excited motional states with the motional ground state. This is an important
application for photon recoil spectroscopy and other force sensing applications
that utilize the high sensitivity of the motional state of trapped ions to
external fields. Furthermore, a determination of the ground state population
enables a simple measurement of the ion's temperature.Comment: 17 pages, 7 figure
Perancangan Interior Science Center Untuk Anak Berusia 3 Sampai 12 Tahun Di Surabaya
Interior design of Science Center for children aged 3 to 12 years in Surabaya is designed to support learning process in formal school, seeing the lack of children\u27s interest in learning because of the unattractive way of learning. Science Center is there to provide an innovative learning facilities with interactive media for children. The design method process is starting from finding out what children need in the science center, then entered the design process, and the last stage is to add small details needed, and each process will be analyzed and evaluated to get the maximal result. In accordance with the concept of “Brain New World”, children is invited to enter the new learning world that is more interesting with various areas and interactive furniture, like touch screen furniture and hologram
Land Cover and Socio-economic Characteristics in the Eight Counties of Alabama: A Spatial Analysis
This study employed a clustering algorithm and a logistic regression analysis to examine the relationship between cropland and demographic attributes obtained at the census block group level. The result indicated that population density, African Americans, and poverty are significantly related with crop land use in the region.Institutional and Behavioral Economics,
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