  We consider an analog of the internal Josephson effect in superfluid atomic
Fermi-gases. Four different hyperfine states of the atoms are assumed to be
trapped and to form two superfluids via the BCS-type pairing. Weshow that
Josephson oscillations can be realized by coupling the superfluids with two
laser fields. Choosing the laser detunings in a suitable way leads to an
asymmetric below-gap tunneling effect for which there exists no analogue in the
context of solid-state superconductivity.
