Aparatus
The Nd-YAG laser served as a pump for the DCM dye laser, which allowed us
to scan through a range of wavelengths (in the red region of the visible spectrum).
The beam was directed into a heatpipe which contained the Cesium in vapor phase.
The ions created by the beam were captured by the anode in the heat pipe. We
put a 9V battery across the cathode and anode. The signal was averaged and
integrated by a boxcar integrator and then passed to a computer.
Diagram of Our Setup
Description of Apparatus
YAG Laser- functions by directing intense flashes of white light in a
crystal that then lases, emitting short pulses of light. In our experiment the laser
was set up to emit short blasts of radiation in the green, which were adequately powerful
enough to excite Cesium.
DCM Dye Laser- The pulses emitted by the YAG laser are directed into a
cavity filled with a circulating dye. The dye is a large, complex molecule with many
different energy levels and possible lasing transistions and is therefore tunable to emit
photons of any desired wavelength within a certain range depending upon the dye.
Since much energy is lost in the lasing process of the oscillatory dye, the pulse is then
directed into another cavity filled with a circulating dye that acts as an
amplifier. The beam passes through the amplifier once. The dye laser adjusts the
wavelength of the original photon pulses and results in a red pulse.
Heat Pipe- This pipe contains Cesium at about 3 torr. The pipe is
heated so that the Cesium goes into the vapor phase. Helium is drawn into the pipe
as well, to serve as shield between the Cesium and the windows of the pipe. This
prevents the Cesium from condensing on the windows.
Table of Contents:
- Main Menu
- Theory: Multi-photon absorption and Raman Scattering
- Data
- Energy Levels
- Procedure and Aparatus