Probing sub-GeV dark matter with TESSERACT

The Transition Edge Sensors with Sub-eV Resolution And Cryogenic Targets (TESSERACT) Collaboration is one of the leading efforts for probing MeV/c^2-scale dark matter. Three target materials will be used to search for particle-like dark matter at these masses: polar sapphire crystals, gallium arsenide, and superfluid helium-4. In tandem, these targets offer competitive sensitivity to dark matter scattering via nuclear and electronic interactions, as well as absorption. This is made possible by coupling the photon and quasiparticle signals produced in the targets to cutting-edge, low-temperature transition edge sensors (TES). I will describe current R&D progress on the TESSERACT project, including technological advancements and development towards the dark matter detectors that TESSERACT plans to run: SPICE and HeRALD.