Damped Rabi oscillations produced by adiabatic pulses in atomic systems

N. N. Bogolyubov, Fam Le Kien, A. S. Shumovskiǐ

Anatoly A. Svidzinsky, Hichem Eleuch, Marlan O. Scully

If an electromagnetic pulse is detuned from atomic transition frequency by amount Δ>1/τ, where τ is the turn-on time of the pulse, then atomic population adiabatically follows the pulse intensity without causing Rabi oscillations. Here we show that, if initially, the atom has nonzero coherence, then the adiabatic pulse yields Rabi oscillations of atomic population ρaa(t), and we obtain analytical solutions for ρaa(t). Our findings can be useful for achieving generation of coherent light in the backward direction in the QASER scheme in which modulation of the coupling between light and atoms is produced by Rabi oscillations. Initial coherence can be created by sending a short resonant pulse into the medium followed by a long adiabatic pulse, which leads to the light amplification in the backward direction.

Leonid E. Kon’kov, Sergey V. Prants

Vasil Z. Vasilev, Benedetto Militello, Anna Napoli +1 more

The quantum state of a traveling light pulse can qualitatively change the excitation dynamics of a two-level atom. We investigate this dependence for coherent and Fock input states using a virtual-cavity formulation with matched input and output temporal profiles. Analytical treatment of the master equation and numerical simulations show that coherent pulses produce damped Rabi oscillations, whereas Fock pulses can exhibit a partial recovery of the oscillation amplitude in the trailing part of the pulse. We examine how coupling to an auxiliary temporal mode and radiative loss shape this recovery. We also establish a connection with stimulated Raman adiabatic passage through an exact many-photon dark state and derive the associated adiabaticity condition. The observed recovery occurs away from ideal dark-state following. These results distinguish transient recovery in traveling-pulse scattering from conventional cavity collapse and revival, and clarify the scope of an adiabatic-transfer interpretation.

Zhenhuan Yi, Xingchen Zhao, Zhiguo Wang +4 more

We experimentally demonstrate that initial atomic coherence yields Rabi oscillations in a two-level system driven by an adiabatic pulse. This method can be used to achieve Quantum Amplification by Superradiant Emission of Radiation (QASER) in atomic vapors.

Vyacheslav Shatokhin, S. Ya. Kilin