Detection
of Rydberg Atoms in Electric Fields via Stimulated Emission
Jonathan
Lenahan Habif
Advisor:
Dr. Enrique J. Galvez, Colgate Unversity
Abstract
Current methods of
Rydberg atom detection consist of ionizing the atoms, and
detecting the electrons or ions from the ionized atoms with a
charged particle detector. Data collected at high values of the
principal quantum number (n>25) produces a signal with a
bandwidth large enough to make populations of neighboring states
in an electric field unresovlveable. By stimulating these atoms
with a photon to emit and decay to a lower energy state, the
linewidth of the data recorded can be limited only by the
linewidth of the laser pulse used in the process, thereby
increasing the resolution of the data by a factor ranging from 10
to 60.
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Jon has
three pulsed (5 nanosecond long) dye laser systems to ajust. All
were assembled by him and Prof. Galvez. Two dye lasers
("yellow" at 589nm and "blue" at 415nm) are
pumped by a Nitrogen laser, exciting atoms in a vacuum system to
Rydberg state (n=20). A third laser ("red" at 642nm) is
pumped by a newly acquired Nd:YAG laser, to generate a delayed
pulse used to detect Rydberg atoms via stimulated decay to a
lower state.
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Each dye
laser has to be tuned, and the resulting laser beams are each
focused with telescopes (one being the two lenses seen in the
foreground) to later be sent to the vacuum chamber. Two of the
beams (yellow and blue) are combined with a dichroic mirror to be
collinear. The third, delayed (red), beam meets the atoms in the
vacuum chamber in opposite direction as the exciting beams.
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