  We introduce a scheme to perform the cooling algorithm, first presented by
Oscar Boykin et al. in 2002, for an arbitrary number of times on the same set
of qbits. We achieve this goal by adding an additional SWAP-gate and a bath
contact to the algorithm. This way one qbit may repeatedly be cooled without
adding additional qbits to the system. By using a product Liouville space to
model the bath contact we calculate the density matrix of the system after a
given number of applications of the algorithm.

Quantum Physics