The coupling between parallel identical chiral slabs has been evaluate
d. The perturbation formula used involves a line integral along a cont
our situated between the guides. The coupling coefficient has been der
ived in the general case. It has been analysed for symmetrical fields
and the conditions for which it vanishes have been established. Graphs
of the normalized coupling coefficient have been given as a function
of the normalized frequency and of the chirality admittance. In genera
l, for a given normalized frequency, the coupling diminishes when the
chirality admittance grows.