Optical pulse delay or advance and frequency tuning with mismatched three-wave interaction

Principally new effects of optical pulse frequency tuning and time delay (advancing) caused by two-pulse collision in a medium with cascaded quadratic nonlinearity are discussed. Thus with the help of cascade interaction it is possible to achieve the total internal reflection of the signal pulse from the pump pulse; after collision optical pulses can be slowed down or accelerated and their frequency can be tuned. It is interesting to note that two separated pump pulses can capture a signal pulse.