  We experimentally perform the simulation of open quantum dynamics in
single-qudit systems. Using a spatial light modulator as a dissipative optical
device, we implement dissipative-dynamical maps onto qudits encoded in the
transverse momentum of spontaneous parametric down-converted photon pairs. We
show a well-controlled technique to prepare entangled qudits states as well as
to implement dissipative local measurements; the latter realize two specific
dynamics: dephasing and amplitude damping. Our work represents a new
analogy-dynamical experiment for simulating an open quantum system.
