PHASE AND RISE-TIME DEPENDENCE USING RF PULSES IN MULTIPHOTON PROCESSES

With this experiment we demonstrate that excitation of a two-stale sys tem with radio-frequency fields differing in phase by 90 degrees produ ces non intuitively different results, even for very long pulses. In a ddition, we show bow the phase dependence of the transition probabilit y of long pulses can he easily understood by using the single cycle ti me propagator. Finally, we have found surprising results for real puls es in the strong-field regime, i.e., pulses having appreciable rise an d fall times.