  A quantum channel is derived for continuous variable teleportation which is
performed by means of an arbitrary entangled state and the standard protocol.
When a Gaussian entangled state such as a two-mode squeezed-vacuum state is
used, the continuous variable teleportation is equivalent to the thermalizing
quantum channel. Continuous variable dense coding is also considered. Both the
continuous variable teleportation and the continuous variable dense coding are
characterized by the same function determined by the entangled state and the
quantum measurement.
