  We analytically calculate the leading quantum corrections of the ground-state
energy of two- and one-dimensional weakly interacting Rabi-coupled Bose-Bose
mixtures in the frame of the Bogoliubov approximation. We show that to
repulsive intraspecies and attractive interspecies interactions, the effect of
quantum fluctuations favors the formation of self-bound droplets. These
liquidlike states are crucially affected by the Rabi coupling, leading thus to
the appearance of a quantum instability. We derive meaningful formulas to
describe the droplet phase in the one-dimensional case.
