| Abstract |
The ability to perform absolute measurements of circular birefringence with high sensitivity
is essential to many disciplines of physics, ranging from searches of new physics beyond the
Strandard Model, to the detection of chiral molecules in biological samples. In this thesis we
describe the principles of a novel cavity-enhanced polarimetric technique used for the absolute
measurement of chirality, by implementing robust background subtraction mechanisms using
two novel signal reversals.
Atomic Parity Non-Conservation (PNC) experiments are complimentary to high-energy particle
physics experiments and have the potential to detect physics beyond the Standard Model. The Standard Model, and extensions of it, predict a weak parity non-conserving transition amplitude
E1PNC between states of the same parity in atomic systems. Measurement of the E1PNC transition amplitude is possible through the interference between a dominant parity-allowed transition. In the vicinity of a parity-allowed magnetic-dipole M1 transition, the interference M1-E1PNC leads to natural optical activity. This dissertation explores the possibility of performing PNC optical rotation studies in three new atomic systems, namely xenon (Xe), mercury (Hg) and iodine (I). The feasibility of obtaining observable signals in various transitions of the proposed atomic systems is discussed in detail, and theoretical simulations are presented, suggesting that PNC measurements with high sensitivity are possible. Furthermore, the ability of performing PNC measurements along a chain of isotopes in all three systems, and measurements of nuclear spin-dependent PNC effects for both odd-neutron and odd-proton nuclei is discussed. The goal of these pursuits is to provide ratios of the observables along the chain of isotopes, from which the details of atomic structure should cancel, and to add measurements of the anapole moments for these three new nuclei, in addition to the only existing measurements in Cs and Tl.
Towards the construction of a PNC optical rotation experiment, various proof-of-principle experiments using pulsed laser sources were performed. In these proof-of-principle experiments,
the absolute measurement of natural optical activity in the gas phase is proved to be possible, using the two novel signal reversals. In particular, measurements of natural optical activity from various chiral molecules in an evacuated and a non-evacuated achiral environment are presented. The open-air gas-phase measurements are realized for the first time. We continue by demonstrating the ability of measuring molecular chirality in the liquid phase using small volume samples, an application of biological interest.
Finally, preliminary studies of a pair of near-degenerate opposite-parity states in atomic Xenon are presented. We examine the possibility of performing experiments in search of parity (P) and time-reversal invariance (T) violating phenomena, and we present Stark-shift measurements of one of the states of interest.
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Cavity-enhanced polarimetry : applications in atomic parity violation and molecular chirality
