  We study how energy transport in an integrable system is affected by the
spectral densities of heat reservoirs. The model investigated here is the
quantum harmonic chain whose both ends are in contact with two heat reservoirs
at different temperatures. The master equation for the reduced density matrix
is derived on the assumption that the reservoirs are composed of an infinite
number of independent harmonic oscillators. We evaluate temperature profile and
energy flux in the stationary state for the master equation and discuss how
they depend on the types of spectral densities. When we attach the reservoirs
of the same type of spectral density, we find that the temperature profile is
independent of the types. On the other hand, when the two reservoirs have
different types of spectral densities, the energy profile near the ends of the
chain depends on the types. When the coupling is finite, the temperature
profile near the ends shows wide variation of behavior dependent on spectral
densities and temperatures of reservoirs. This dependence is discussed with the
Fokker-Planck equations obtained in the classical limit.
