We report a study of the optical dipole force on a beam of neutral three-level, $\ensuremath{\Lambda}$-like atomic system induced by a femtosecond super-Gaussian pulse. We show that maximum coherence between the ground state $|1\ensuremath{\rangle}$ and the excited state $|2\ensuremath{\rangle}$ could be achieved using a train of femtosecond pulses. In addition, it is possible to control the trajectory of the atoms in an atomic beam by using the same scheme. The robustness of the scheme against the variation of the pulse parameters is also investigated.
We report a study on the ultrafast coherent population oscillations (UCPOs) in two-level atoms induced by a frequency-modulated few-cycle optical pulse train. The phenomenon of UCPOs is investigated by numerically solving the optical Bloch equations beyond the rotating wave approximation. We demonstrate that the quantum state of the atoms and the frequency of the UCPOs may be controlled by controlling the number of pulses in the pulse trains and the pulse repetition time, respectively. Moreover, the robustness of the population inversion against the variation of the laser pulse parameters is also investigated. The proposed scheme may be useful for the creation of atoms in selected quantum states for desired time duration and may have potential applications in ultrafast optical switching. The scheme may also be used to measure pulse repetition rate.
We develop a pulse-driven jump protocol to achieve all-optical Raman control of ultracold atomic hyperfine states. By establishing general conditions for adiabatic evolution between quantum states in parameter space, we derive the essential pulse area and phase conditions necessary for quantum state transfer in a resonant single-
Λ three-level system. We extend this approach to a double-
Λ four-level system by incorporating a neighboring intermediate state, which leads to a single-photon detuned
Λ three-level system. Through numerical simulations of the ultracold
87Rb atomic system, we demonstrate that high-fidelity and robust control of quantum state transfer can be achieved in the single-
Λ three-level system using stimulated Raman adiabatic passage (STIRAP) and the pulsed jump protocol. Furthermore, we show that the destructive quantum interference effects between resonant and detuned Raman pathways in the double-
Λ four-level system can be mitigated by optimizing the pulse area and two-photon detuning parameters within the pulsed jump protocol. This work presents a promising approach for achieving all-optical Raman control of quantum state transfer in ultracold atomic hyperfine states.