Studies of atomic response to phase-diffusion laser fields

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1992

OSTI ID:6923533

Anderson, M H

This thesis describes two experiments concerning the response of two-level atoms driven by phase diffusing fields. The frequency fluctuations of the driving field are imposed with a system of electro-optics. In the first experiment, noise induced population fluctuations of the upper state were observed by measuring the variance of fluorescence intensity fluctuations emitted by a large number of atoms near resonance with the phase diffusing laser. In addition, the spectrum of the fluorescence intensity fluctuations has been measured. The variance and spectrum were measured as functions of the laser bandwidth and the bandwidth of the laser frequency fluctuations. The variance and spectrum were measured as functions of the laser power and detuning, and statistical parameters such as the laser bandwidth and the bandwidth of the laser frequency fluctuations. The variance and spectrum are shown to be more sensitive to the statistics of the laser field than the time averaged fluorescence intensity. In the second experiment, the absorption of a weak probe laser, due to atoms that are saturated by a strong pump laser, is measured as a function of a time delay between the pump and probe. The pump and probe are derived from the same phase-diffusing laser, but are time delayed replicas of each other, and together they form a non-Markovian driving field. The experiment is carried out in the regime where the Rabi frequency of the pump field is comparable to field bandwidth. Amplification of the probe field is observed and shown to be induced by the phase noise in conjugation with a time delay. The results of both experiments are compared with theoretical calculations based on stochastic averages of the Optical Bloch equations and are shown to be in excellent agreement.

• Research Organization: Colorado Univ., Boulder, CO (United States)
• OSTI ID: 6923533
• Country of Publication: United States
• Language: English

Related Subjects

664200* -- Spectra of Atoms & Molecules & their Interactions with Photons-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ATOMS
BEAM DYNAMICS
BLOCH EQUATIONS
ELECTRO-OPTICAL EFFECTS
ELECTROMAGNETIC RADIATION
EQUATIONS
FLUORESCENCE
FUNCTIONS
LASER RADIATION
LUMINESCENCE
MECHANICS
OSCILLATIONS
PHASE OSCILLATIONS
RADIATIONS
RESPONSE FUNCTIONS
STATISTICAL MECHANICS