Parker Solar Probe observations near the Sun reveal frequent, sudden reversals of the magnetic field known as switchbacks (SBs). Despite their ubiquity, the internal plasma structure and associated heating within SBs remain poorly understood. We present a case study of two closely spaced SBs (referred to in the text as ${\mathrm{SB}}_1$ and ${\mathrm{SB}}_2$) observed on 24 January 2020 using high-cadence magnetic and plasma measurements. Magnetic fluctuations are decomposed into components parallel and perpendicular to the mean field, and their power spectra are analyzed to characterize the turbulent cascade. The partial variance of increments method is applied to identify intermittent current sheetlike features. Both SB intervals exhibit clear Alfvénic behavior and enhanced radial flow; however, their microphysics differ: ${\mathrm{SB}}_1$ shows a higher proton temperature, larger fluctuation amplitudes, and a denser population of current sheets compared to ${\mathrm{SB}}_2$. The two events also differ in spectral index, with ${\mathrm{SB}}_1$ exhibiting a steeper perpendicular slope than ${\mathrm{SB}}_2$. The elevated intermittency, proton temperature, and transient $\beta >1$ excursion in ${\mathrm{SB}}_1$ suggest that localized dissipation at small-scale structures is a plausible driver of the observed heating. These findings demonstrate that SBs are not uniform kinematic deflections but dynamically evolving plasma structures whose internal turbulence may regulate local energy conversion and contribute to the spatially intermittent heating of the near-Sun solar wind.

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• Plasma turbulence
• Space science
• Space & astrophysical plasma