We present a purely theoretical, fully analytical momentum-space description of “superkick” momentum transfer to a two-level atom driven by a tightly focused, circularly polarized Laguerre-Gaussian vortex beam. Using the short-time excitation amplitude ${\psi }_e(\mathbf{r},t)\propto E_z\left(\mathbf{r}\right){\psi }_g\left(\mathbf{r}\right)$ and an exact Fourier-transform treatment in the near-focus regime, we derive closed-form expressions for the excited-state wave function ${\tilde{\psi }}_e\left(\mathbf{K}\right)$ and its momentum distribution $|{\tilde{\psi }}_e{\left(\mathbf{K}\right)|}^2$. This framework yields direct superkick diagnostics such as peak displacement and transverse-momentum moments, and enables a systematic comparison between opposite-handedness and same-handedness configurations, as well as a paraxial reference case. We show that tight focusing, through the longitudinal-field enhancement, strongly increases the near-axis excitation and makes superkick signatures most prominent in the opposite-handedness configuration, whereas the same-handedness and paraxial reference cases retain related transverse superkick structure but carry much smaller near-axis probability weight.

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• Angular momentum of light
• Cold atoms & matter waves
• Light-matter interaction
• Optical vortices
• Structured light
• Two-level systems