  Conventional wisdom holds that quantum effects are fragile and can be
destroyed by loss. Here, contrary to general belief, we show how to realize
quantum revival of optical correlations at the single-photon level with the
help of loss. We find that, accompanying loss-induced transparency of light in
a nonlinear optical-molecule system, quantum suppression and revival of
photonic correlations can be achieved. Specifically, below critical values,
adding loss into the system leads to suppressions of both optical intensity and
its non-classical correlations; however, by further increasing the loss beyond
the critical values, quantum revival of photon blockade (PB) can emerge,
resulting in loss-induced switch between single-PB and two-PB or
super-Poissonian light. Our work provides a strategy to reverse the effect of
loss in fully quantum regime, opening up a counterintuitive route to explore
and utilize loss-tuned single-photon devices for quantum technology.
