  We study the problem of heat conduction in a mass-disordered two-dimensional
harmonic crystal. Using two different stochastic heat baths, we perform
simulations to determine the system size (L) dependence of the heat current
(J). For white noise heat baths we find that J ~ 1/L^a with $ a \approx 0.59 $
while correlated noise heat baths gives $ a \approx 0.51 $. A special case with
correlated disorder is studied analytically and gives a=3/2 which agrees also
with results from exact numerics.
