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Cataclysmic variables (CVs) that have evolved past the period minimum duringtheir lifetimes are predicted to be systems with a brown dwarf donor. Whilepopulation synthesis models predict that around $\approx 40-70\%$ of theGalactic CVs are post-period minimum systems referred to as "period bouncers",only a few dozen confirmed systems are known. We report the study andcharacterisation of a new eclipsing CV, SRGeJ041130.3+685350 (SRGeJ0411),discovered from a joint SRG/eROSITA and ZTF program. The optical spectrum ofSRGeJ0411 shows prominent hydrogen and helium emission lines, typical for CVs.We obtained optical high-speed photometry to confirm the eclipse of SRGeJ0411and determine the orbital period to be $P_\textrm{orb} \approx 97.530$ minutes.The spectral energy distribution suggests that the donor has an effectivetemperature of $\lesssim 1,800$ K. We constrain the donor mass with theperiod--density relationship for Roche-lobe-filling stars and find that$M_\textrm{donor} \lesssim 0.04\ M_\odot$. The binary parameters are consistentwith evolutionary models for post-period minimum CVs, suggesting that SRGeJ0411is a new period bouncer. The optical emission lines of SRGeJ0411 aresingle-peaked despite the system being eclipsing, which is typically only seendue to stream-fed accretion in polars. X-ray spectroscopy hints that the whitedwarf in SRGeJ0411 could be magnetic, but verifying the magnetic nature ofSRGeJ0411 requires further investigation. The lack of optical outbursts hasmade SRGeJ0411 elusive in previous surveys, and joint X-ray and optical surveyshighlight the potential for discovering similar systems in the near future.

A Joint SRG/eROSITA + ZTF Search: Discovery of a 97-min Period Eclipsing Cataclysmic Variable with Evidence of a Brown Dwarf Secondary