  We present the first instance of a disorder tuned Fermi-Bose crossover that
could be realized in superconducting systems. More specifically, harnessing a
non perturbative numerical technique we analyze the ground state behavior of a
two-dimensional attractive Hubbard model subjected to spin selective disorder
potential. In particular, using spectroscopic properties we provide unambiguous
evidence of the change in the Fermi surface topology as a function of the
disorder, establishing incontrovertibly a Fermi-Bose crossover. Interplay of
strong correlations and strong disorder brings out the spin selectivity in the
properties of this system giving rise to spin selective "Bose metal/insulator"
phase. We propose an experimental set-up where such disorder tuned Fermi-Bose
crossover could be observed in two-dimensional electron gas formed at oxide
interface. Finally, we speculate on the possible implication of such
spin-selective disorder on unraveling signatures of Bose-Fermi cross-over on
doped iron chalcogenide superconductors.
