72 research outputs found
Accurate Calibration Of The Beam Energy In A Storage Ring based On measurement Of Spin Precession Frequency Of Polarized Particles
Steady state of atoms in a resonant field with elliptical polarization
We present a complete set of analytical and invariant expressions for the
steady-state density matrix of atoms in a resonant radiation field with
arbitrary intensity and polarization. The field drives the closed dipole
transition with arbitrary values of the angular momenta and of
the ground and excited state. The steady-state density matrix is expressed in
terms of spherical harmonics of a complex direction given by the field
polarization vector. The generalization to the case of broad-band radiation is
given. We indicate various applications of these results.Comment: revtex, 26 pages, including 3 eps figures; PRA accepted for
publication;v2 three typos are fixe
Dissipative light field as a way to create strongly localized structures for atom lithography
Generally, the conditions for deep sub-Doppler laser cooling do not match the
conditions for the strong atomic localization that takes a place in deeper
optical potential and, in consequence, leads to larger temperature. Moreover,
for a given detuning in a deep optical potential the secular approximation
which is usually used for quantum description of laser cooling becomes no more
valid. Here we perform an analysis of atomic localization in optical potential
based on a full quantum approach for atomic density matrix. We also show that
the laser cooling in a deep far-off detuned optical potential, created by a
light field with a polarization gradient, can be used as an alternative method
for forming high contrast spatially localized structures of atoms for the
purposes of atom lithography and atomic nanofabrication. Finally, we perform an
analysis of the possible limits for the width and the contrast of localized
atomic structures that can in principle be reached by this type of the light
mask.Comment: 4 figure
Microwave Spectroscopy of Cold Rubidium Atoms
The effect of microwave radiation on the resonance fluorescence of a cloud of
cold atoms in a magnetooptical trap is studied. The radiation
frequency was tuned near the hyperfine splitting frequency of rubidium atoms in
the 5S ground state. The microwave field induced magnetic dipole transitions
between the magnetic sublevels of the 5S(F=2) and 5S(F=3) states, resulting in
a change in the fluorescence signal. The resonance fluorescence spectra were
recorded by tuning the microwave radiation frequency. The observed spectra were
found to be substantially dependent on the transition under study and the
frequency of a repump laser used in the cooling scheme.Comment: 6 pages, 4 figure
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