Detection and transit time measurements of individual sodium atoms diffusing in a helium flow by the laser resonance fluorescence correlation technique

This thesis describes the laser resonance fluorescence correlation technique for single-atom velocity measurement. Using this technique, we have detected individual sodium atoms diffusing through a laser beam in a slow helium flow. From the width of the fluorescence bursts detected, the transit time for the diffusing atom is determined. This is the first measurement of the motion of a single atom in a buffer gas. A probability analysis was developed which allowed us to estimate the average burst size of emitted fluorescence photons by an atom traversing the laser beam. All these results were in general agreement with the theoretical predictions. With improvements, we will be able to measure the velocity of a single-atom either in a flow or in a vacuum. By averaging over many sodium atoms, the diffusion coefficients of sodium atoms in helium and argon buffer gases were investigated using this technique. The measured diffusion coefficients were found to be in reasonable agreement with theoretical predictions and previous experimental results. To our knowledge, this is the first application of resonance fluorescence correlation technique to the measurement of diffusion coefficient of fast moving atoms in gases.

Name thesis:degree_name

Doctor of Philosophy (Ph.D.)

Level thesis:degree_level

Doctoral

Discipline thesis:degree_discipline

Physics

Grantor dc:publisher

Colorado State University. Libraries

Year dc:date.issued

1979

Authors dc:creator

• Pan, Ci-Ling, author
• She, C. Y., advisor

• Atoms
• Laser spectroscopy

Statement dc:rights

• Copyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.

Language dc:language.iso

eng, English

Identifier URI

https://doi.org/10.25675/3.025026

OAI record oai:identifier

https://api.mountainscholar.org/server/oai/request?verb=GetRecord&metadataPrefix=dim&identifier=oai%3Amountainscholar.org%3A10217%2F240466