The project presented in this thesis pertains to the intersection of atomic and nuclear
physics, specifically, laser trapping techniques applied to caesium isotopes and isomers.
The main experiment is a laser cooling apparatus installed at the Ion Guide
Isotope Separation On-Line (IGISOL) facility at the University of Jyväskylä, Finland.
When training or during delays in the primary experiment, I often worked
on experiments based at UCL. The first section describes a 133Cs Magneto-Optical
Trap (MOT) experiment at UCL, and was used as an analogue to the isomer trapping
experiment. The laser system was set up, and the vacuum chamber was prepared
for the MOT, which was then characterised.
Then the isomer cooling experiment is discussed. Due to a power cut, many
parts of the laser system had to be repaired. The apparatus was then tested – firstly
by obtaining a 133Cs MOT from an ampoule, then from an offline 133Cs+ ion beam.
The experiment was further developed by establishing an offset frequency locking
scheme for the laser sources. This will allow the laser frequencies to be varied for
various isotopes and isomers. Frequency offsets from 200 MHz to 9.9 GHz were
successfully locked to. The final section reports on an atomic magnetometer, which
uses cold atoms instead of atoms at or close to room temperature. A sensitivity of
330 pT/
√
Hz with an operational range of 15 – 100 kHz was achieved and the result
was published in [1].
Future progress is expected to include the trapping of 134Cs, the beam for
which shall be produced via 134CsNO3 samples from Institut Laue–Langevin (ILL).
Long term goals include the trapping of the 135mCs isomer, and eventually a Bose Einstein Condensate (BEC) of the isomer. This will allow the exploration of the
generation of coherent gamma photons, which has many possible applications,
ranging from biomedicine to fundamental studies on multi-body phenomena.