title: Continuous and pulsed quantum zeno effect.
abstract: Continuous and pulsed quantum Zeno effects were observed using a 87Rb Bose-Einstein condensate. Oscillations between two ground hyperfine states of a magnetically trapped condensate, externally driven at a transition rate omega(R), were suppressed by destructively measuring the population in one of the states with resonant light. The suppression of the transition rate in the two-level system was quantified for pulsed measurements with a time interval deltat between pulses and continuous measurements with a scattering rate gamma. We observe that the continuous measurements exhibit the same suppression in the transition rate as the pulsed measurements when gammadeltat=3.60(0.43), in agreement with the predicted value of 4. Increasing the measurement rate suppressed the transition rate down to 0.005 omega(R).
authors.affiliation: Department of Physics, MIT-Harvard Center for Ultracold Atoms, and Research Laboratory of Electronics, MIT, Cambridge, Massachusetts 02139, USA.
authors.forename: Erik W
authors.initials: EW
authors.lastname: Streed
authors.forename: Jongchul
authors.initials: J
authors.lastname: Mun
authors.forename: Micah
authors.initials: M
authors.lastname: Boyd
authors.forename: Gretchen K
authors.initials: GK
authors.lastname: Campbell
authors.forename: Patrick
authors.initials: P
authors.lastname: Medley
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Ketterle
authors.forename: David E
authors.initials: DE
authors.lastname: Pritchard