The existence of physics beyond the standard model (BSM) is established with the observation of neutrino flavor oscillations. Germanium detectors with their excellent energy response and sub-keV sensitivities  provide a unique tool to probe a class of BSM scenarios. The TEXONO Collaboration  has been pursuing these studies experimentally, complemented by adaptation of advanced atomic physics theory techniques to derive neutrino interaction cross-sections at atomic-scale energy. We will present highlights of the studies on neutrino electromagnetic interactions  as well as constraints on sterile neutrinos, axions and dark photons . Additional subjects along these lines will also be discussed.
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