  Quantum antiferromagnets on geometrically frustrated lattices have long
attracted interest for the formation of quantum disordered states and the
possible emergence of quantum spin liquid (QSL) ground states. Here we turn to
the nearest-neighbor spin-$1/2$ Heisenberg antiferromagnet on the maple-leaf
lattice, which is known to relieve frustration by the formation of canted
$120^{\circ}$ magnetic order or valence bond crystal order when varying the
bond anisotropy. Employing a pseudo-fermion functional renormalization group
approach to assess its ground state phase diagram in detail, we present
evidence for a QSL regime sandwiched between these two limiting phases. The
formation of such a QSL might signal proximity to a possible deconfined quantum
critical point from which it emerges, and that is potentially accessible by
tuning the exchange couplings. Our conclusions are based on large-scale
simulations involving a careful finite-size scaling analysis of the behavior of
magnetic susceptibility and spin-spin correlation functions under
renormalization group flow.
