Quantum dynamics of a two-state system induced by a chirped zero-area pulse

Abstract

It is well known that area pulses make Rabi oscillation and chirped pulses in the adiabatic interaction regime induce complete population inversion of a two-state system. Here we show that chirped zero-area pulses could engineer an interplay between the adiabatic evolution and Rabi-like oscillations. In a proof-of-principle experiment utilizing spectral chirping of femtosecond laser pulses with a resonant spectral hole, we demonstrate that the chirped zero-area pulses could induce, for example, complete population inversion and return of the cold rubidium atom two-state system. Experimental result agrees well with the theoretically considered overall dynamics, which could be approximately modeled to a Ramsey-like three-pulse interaction, where the x-and z-rotations are respectively driven by the hole and the main pulse.

Selective excitation in a three-state system using a hybrid adiabatic-nonadiabatic interaction

“…Note that similar coupling and detuning terms are discussed in the context of the zero-area pulse interaction with a two-level system [25].…”

“…Broadband light sources greatly benefit optical approaches to qubit manipulations because of their powerful pulse-shape programming capability [19,20]. In ultrafast optics, composing the amplitude and phase of a broadband laser pulse provides various complex pulse shapes, and their usage often plays a crucial role in investigating and engineering new quantum dynamics of atoms and molecules [21][22][23][24][25][26]. Of particular relevance in the context of the present paper is the selective population method of dressed states (SPODS) [26] which provides a pulse shaping scheme especially in the frequency domain for strong-field controls of multilevel systems.…”

Single-laser-pulse implementation of arbitrary ZYZ rotations of an atomic qubit

“…3). The detail of our laser experimental setup is described in our previous work [13,14]. Briefly, we used amplified optical pulses from a Ti:sapphire mode-locked laser.…”

Achieving robust and high-fidelity quantum control via spectral phase optimization

“…Clearly, the diabatic energy levels in the absence of Ω(t) will take place an exact crossing when the energy level is swept. In the presence of Ω(t), however, the adiabatic energy levels E ± (t) = ± Ω 2 (t) + ∆ 2 (t)/2 obtained by diagonalizing Ĥdia will form an avoided crossing by slowly chirping the instantaneous frequency of the control field with a large enough chirp rate β 0 combined with a large enough Rabi frequency Ω(t), i.e., the adiabatic condition of | θ(t)| ≪ ∆ 2 (t) + Ω 2 (t) is maintained [29,46,60]. The corresponding adiabatic eigenstates can be given by |+ = sin ϑ(t)|1 e iϕ + cos ϑ(t)|2 and |− = cos ϑ(t)|1 e iϕ − sin ϑ(t)|2 with a mixing angle ϑ(t) = tan −1 (Ω(t)/∆(t))/2.…”