Noble-liquid detectors,
employing liquid xenon or liquid argon as their target material, are at the
forefront of current searches for Dark Matter and other rare-event processes. Their
operation relies on the detection of feeble UV light signals, emitted when
incoming particles interact inside their liquid core. To suppress background,
the experiments are operated deep underground, use only radio-pure materials and
employ a combination of passive and active shielding schemes. The use of noble
liquids allows for a large volume of homogeneous scintillation material of
extremely high purity, where the emitted photons can travel to large distances
and be detected by an array of UV-sensitive photon detectors surrounding the
active region. By additionally detecting ionization electrons released at the
site of interaction, one can determine its spatial coordinates, the deposited
energy and the identity of the incoming particle, thus discriminating signal
from residual background events. Since the sensitivity of noble-liquid
detectors generally scales as the product of their active mass and exposure
time, progressively larger detectors are being designed and deployed, setting
increasingly more challenging requirements for their realization. We discuss
two concepts developed at the Weizmann Institute for detection techniques which
aim to meet these requirements, thus allowing for significant improvements in present
schemes and enable the design of future, highly sensitive multi-ton experiments.