  A novel concept is proposed for large-volume single-phase noble-liquid TPC
detectors for rare events. Both radiation-induced scintillation-light and
ionization-charge are detected by Liquid Hole-Multipliers, LHM, immersed in the
noble liquid. The latter may consist of cascaded Gas Electron Multipliers
(GEM), Thick Gas Electron Multiplier (THGEM) electrodes or others, coated with
CsI UV-photocathodes. Electrons, photo-induced on CsI by primary scintillation
in the noble liquid, and event-correlated drifting ionization electrons are
amplified in the cascaded elements primarily through electroluminescence, and
possibly through additional moderate avalanche, occurring within the holes. The
resulting charge-signals or light-pulses are recorded on anode pads or with
photosensors, e.g. gaseous photomultipliers (GPM), respectively. Potential
affordable solutions are proposed for multi-ton dark-matter detectors; open
questions are formulated for validating this dream.
