Passive switch for 1.315 μ radiation

The physical basis of the operation of an atomic iodine passive switch (for iodine photodissociation lasers) is considered. Atomic iodine is obtained by thermal dissociation of I₂. An experimental dependence of the switch transmission on the radiation intensity is reported; it is in satisfactory agreement with the theory. A weak-signal attenuation by a factor of ~ 100 is achieved for 70–80% transmission of a saturating signal (I~5×10⁸ W/cm²). It is shown that a switch of this kind can be used as a decoupler in multistage amplifying systems.