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We report measurements of the ratio of the scalar polarizability $$\alpha$$ to the vector polarizability $$\beta$$ for the $$6s ^2S_{1/2} \rightarrow 7s ^2S_{1/2}$$ transition in atomic cesium. These measurements are motivated by a discrepancy between the values of the vector transition polarizability as determined using two separate methods. In the present measurement, we use a two-pathway, coherent-control technique in which we observe the interference between a two-photon interaction driven by infrared light at 1079 nm and a linear Stark-induced interaction driven by the mutually-coherent second harmonic of this infrared beam at 540 nm. The result of our measurements is $$\alpha/\beta = -9.902 \: (9)$$, in good agreement with the previous determination of this ratio. This measurement, critical to the study of atomic parity violation in cesium, does not reduce the discrepancy between the two methods for the determination of the vector polarizability $$\beta$$ for this transition. 

We report a new precision measurement of the dc Stark shift of the $$6s\hspace{1mm} ^2S_{1/2} \rightarrow 7s\hspace{1mm}^2S_{1/2}$$ transition in atomic cesium-133. Our result is 0.72246 (29) $$\textrm{Hz}(\textrm{V}/\textrm{cm})^{-2}$$. This result differs from a previous measurement of the Stark shift by $$\sim$$0.5\%, or 4.7$$\sigma$$. We use this value to recalculate the magnitude of the reduced dipole matrix elements $$\langle7s ||r||7p_{j}\rangle$$, as well as the vector transition polarizability for the $$6s \rightarrow 7s$$ transition, $$\tilde{\beta} = 27.043 \: (36) \ a_0^3$$. This determination helps resolve a critical discrepancy between two techniques for determining the vector polarizability. 

We report progress toward measurements of the electric dipole (E1) transition moments between hyperfine components of the ground state of atomic cesium. This transition is weakly E1 allowed due to weak interactions between nucleons within the nucleus, which lead to a parity-odd current distribution and its associated anapole moment. In this report, we discuss the experimental geometry of our measurement scheme, explore the effects of extraneous fields that can obscure the signal, present initial measurements, analyze the sources and magnitudes of measurement noise, and suggest improvements to the current apparatus. 

We report measurements of the absolute energies of the hyperfine components of the $$12s \ ^2S_{1/2}$$ and $$13s \ ^2S_{1/2}$$ levels of atomic cesium, $$^{133}$$Cs. Using the frequency difference between these components, we determine the hyperfine coupling constants for these states, and report these values with a relative uncertainty of $$\sim$$0.06\%. We also examine the hyperfine structure of the $$11d \ ^2D_{J}$$ ($J=3/2, 5/2$) states, and resolve the sign ambiguity of the hyperfine coupling constants from previous measurements of these states. We also derive new, high precision values for the state energies of the $$12s \ ^2S_{1/2}$$, $$13s \ ^2S_{1/2}$$ and $$11d \ ^2D_{J}$$ states of cesium.