  The classical XXZ triangular-lattice antiferromagnet (TAF) shows both an
Ising and a BKT transition, related to the chirality and the in-plane spin
components, respectively. In this paper the quantum effects on the
thermodynamic quantities are evaluated by means of the pure-quantum
self-consistent harmonic approximation (PQSCHA), that allows one to deal with
any spin value through classical MC simulations. We report the internal energy,
the specific heat, and the in-plane correlation length of the quantum XX0 TAF,
for S=1/2, 1, 5/2. The quantum transition temperatures turn out to be smaller
the smaller the spin, and agree with the few available theoretical and
numerical estimates.
