The evolution and revival structure of angular momentum quantum wave packets (Tutorial)

In this paper a coherent superposition of angular momentum states created by absorption of polarized light by molecules is analyzed. Attention is paid to the time evolution of wave packets representing spatial orientation of internuclear axis of diatomic molecule. Two examples are considered in detail. Molecules absorbing light in a permanent magnetic field experiencing Zeeman effect and molecules absorbing light in a permanent electric field experiencing quadratic Stark effect. In a magnetic field we have a wave packet that evolves in time exactly as classical dipole oscillator in a permanent magnetic field. In the second case we have the wave packet that goes through periodical changes of a shape of the packet and revivals of initial shape. This is a pure quantum behavior. Classical motion of angular momentum in an electric field in case of quadratic Stark effect is known to be aperiodic. Obtained solutions for wave packet evolution are briefly compared with Rydberg state coherent wave packets and harmonic oscillator wave packets.Comment: LaTeX, 3 figure

Angular momentum spatial distribution symmetry breaking in Rb by an external magnetic field

Excited state angular momentum alignment -- orientation conversion for atoms with hyperfine structure in presence of an external magnetic field is investigated. Transversal orientation in these conditions is reported for the first time. This phenomenon occurs under Paschen Back conditions at intermediate magnetic field strength. Weak radiation from a linearly polarized diode laser is used to excite Rb atoms in a cell. The laser beam is polarized at an angle of pi/4 with respect to the external magnetic field direction. Ground state hyperfine levels of the 5S_1/2 state are resolved using laser-induced fluorescence spectroscopy under conditions for which all excited 5P_3/2 state hyperfine components are excited simultaneously. Circularly polarized fluorescence is observed to be emitted in the direction perpendicular to both to the direction of the magnetic field B and direction of the light polarization E. The obtained circularity is shown to be in quantitative agreement with theoretical predictions.Comment: Accepted for publication in Phys. Rev.

Cascade coherence transfer and magneto-optical resonances at 455 nm excitation of Cesium

We present and experimental and theoretical study of nonlinear magneto-optical resonances observed in the fluorescence to the ground state from the 7P_{3/2} state of cesium, which was populated directly by laser radiation at 455 nm, and from the 6P_{1/2} and 6P_{3/2} states, which were populated via cascade transitions that started from the 7P_{3/2} state and passed through various intermediate states. The laser-induced fluorescence (LIF) was observed as the magnetic field was scanned through zero. Signals were recorded for the two orthogonal, linearly polarized components of the LIF. We compared the measured signals with the results of calculations from a model that was based on the optical Bloch equations and averaged over the Doppler profile. This model was adapted from a model that had been developed for D_1 and D_2 excitation of alkali metal atoms. The calculations agree quite well with the measurements, especially when taking into account the fact that some experimental parameters were only estimated in the model.Comment: small changes to text of previous version; 12 pages, 8 figure

Dynamic effects in nonlinear magneto-optics of atoms and molecules

A brief review is given of topics relating to dynamical processes arising in nonlinear interactions between light and resonant systems (atoms or molecules) in the presence of a magnetic field.Comment: 15 pages, 11 figure

Dichroic atomic vapor laser lock with multi-gigahertz stabilization range

A dichroic atomic vapor laser lock (DAVLL) system exploiting buffer-gas-filled millimeter-scale vapor cells is presented. This system offers similar stability as achievable with conventional DAVLL system using bulk vapor cells, but has several important advantages. In addition to its compactness, it may provide continuous stabilization in a multi-gigahertz range around the optical transition. This range may be controlled either by changing the temperature of the vapor or by application of a buffer gas under an appropriate pressure. In particular, we experimentally demonstrate the ability of the system to lock the laser frequency between two hyperfine components of the $^{85}$Rb ground state or as far as 16 GHz away from the closest optical transition.Comment: 11 pages, 7 figures. Published in Review of Scientific Instruments 201

Implementation of a double-scanning technique for studies of the Hanle effect in Rubidium vapor

We have studied the resonance fluorescence of a room-temperature rubidium vapor exited to the atomic 5P3/2 state (D2 line) by powerful single-frequency cw laser radiation (1.25 W/cm^2) in the presence of a magnetic field. In these studies, the slow, linear scanning of the laser frequency across the hyperfine transitions of the D2 line is combined with a fast linear scanning of the applied magnetic field, which allows us to record frequency-dependent Hanle resonances from all the groups of hyperfine transitions including V- and Lambda - type systems. Rate equations were used to simulate fluorescence signals for 85Rb due to circularly polarized exciting laser radiation with different mean frequency values and laser intensity values. The simulation show a dependance of the fluorescence on the magnetic field. The Doppler effect was taken into account by averaging the calculated signals over different velocity groups. Theoretical calculations give a width of the signal peak in good agreement with experiment