The physics potential of EDELWEISS detectors for the search of low-mass Weakly Interacting Massive Particles ( WIMPs ) is studied .
Using a data-driven background model , projected exclusion limits are computed using frequentist and multivariate analysis approaches , namely profile likelihood and boosted decision tree .
Both current and achievable experimental performance are considered .
The optimal strategy for detector optimization depends critically on whether the emphasis is put on WIMP masses below or above \sim 5 GeV/c ^ { 2 } .
The projected sensitivity for the next phase of the EDELWEISS-III experiment at the Modane Underground Laboratory ( LSM ) for low-mass WIMP search is presented .
By 2018 an upper limit on the spin-independent WIMP-nucleon cross-section of \sigma _ { SI } = 7 \times 10 ^ { -42 } cm ^ { 2 } is expected for a WIMP mass in the range 2 - 5 GeV/c ^ { 2 } .
The requirements for a future hundred-kilogram scale experiment designed to reach the bounds imposed by the coherent scattering of solar neutrinos are also described .
By improving the ionization resolution down to 50 eV _ { ee } , we show that such an experiment installed in an even lower background environment ( e.g .
at SNOLAB ) should allow to observe about 80 ^ { 8 } B neutrino events after discrimination .