RESUMO
Guided systems for coherent matter waves are expected to offer substantial improvements over unguided systems, but adiabatic coupler proposals have proven difficult to realize. We outline instead considerations for a coherence-preserving diabatic approach enabling filters, couplers, and interferometers that can accept multimode guide inputs of up to magneto-optical-trap temperatures.
RESUMO
The phase space density of dense, cylindrical clouds of atoms in a 2D magneto-optic trap is investigated. For a large number of trapped atoms (>10(8)), the density of a spherical cloud is limited by photon reabsorption. However, as the atom cloud is deformed to reduce the radial optical density, the temperature of the atoms decreases due to the suppression of multiple scattering leading to an increase in the phase space density. A density of 2 x 10(-4) has been achieved in a magneto-optic trap containing 2 x 10(8) atoms.
RESUMO
We present a calculation of the force on a stationary three-level atom excited by a nearly resonant Raman light field, which may be composed of an arbitrary combination of standing- and traveling-wave fields. The effects of the ground-state coherences are explicitly included and are shown to play a crucial role in the nature of the force on the atom. We show that the force contains terms that vary on length scales both shorter and longer than the optical wavelength and that the magnitude of these terms can be made arbitrarily large.
RESUMO
Line shapes observed when direct laser absorption is used in an atomic beam of sodium show asymmetries not present in fluorescence detection. Such line-shape distortion, which can be explained by resonant light diffraction by the atoms in the atomic beam, may be eliminated by imaging the fields in the interaction region at the surface of a detector located outside the beam apparatus.
RESUMO
As part of a program to develop sensitive laser inertial rotation sensors, we have studied the performance of a passive-resonator technique using a 0.7-m x 0.7-m optical cavity. For an averaging time tau of 10 sec, the random drift was 1.1 x10(-2) deg/h, which was consistent with the shot-noise limit for the present setup. For a longer averaging time the random drift was 5.6 x 10(-3) deg/h (tau = 90 sec), showing a slight departure from the shot-noise limit. The problems encountered in the present apparatus, as well as those that are critical in the development of much larger esonators for geophysics and relativity applications, are discussed.