Frequency Domain Control by the Autler-Townes Effect

Yu Bai

Imran Ali, Changbiao Li, Abdulkhaleq Hasan +4 more

For first time, we study primary and secondary Autler-Townes (AT) splitting of multi-order fluorescence (FL) in time domain. The AT-splitting of multi-order FL signals are controlled by changing power, detuning, and polarization of single and double dressing in a heteronuclear-like molecule system of Pr+3:YSO. The primary and secondary AT-splitting is caused by double cascaded dressing in time domain. The AT-splitting of multi-order FL in time domain is more sensitive than that of in spectral domain. Such results have potential applications in quantum communication and optical information processing on photonic chip.

Miloslav Dušek

Mengxi Wu, Shaohao Chen, Mette B. Gaarde +1 more

We present a theoretical study of the delay-dependent Autler-Townes (AT) splitting in transient absorption spectroscopy of an isolated attosecond pulse in helium atoms subject to a delayed infrared (IR) pulse. We concentrate on cases in which the IR pulse is resonant with the helium $1s2p\text{\ensuremath{-}}1s2s$ transition and provide a time-domain perspective of the dynamics in the delay-dependent pump-probe system. We identify several interesting delay-dependent features in the transient absorption spectrum such as AT splitting, oscillation between absorption and emission at the resonant absorption frequency, and sub-IR-cycles oscillations. We then explain the origins of these features in the time domain in terms of a strongly driven two-level system, in the language of population transfer and coherent control.

Mikhail A. Noginov

Jinhong Liu, Jinze Wu, Yueying Zhang +2 more

Electromagnetically induced transparency is a quantum interference (QI) effect in a coherent system, in which the similar but distinct effect of Autler–Townes splitting (ATS) without QI also happens concurrently. The Akaike information criterion (AIC) has been proven to be an efficient and objective method to discern them by evaluating their relative AIC weights for different Rabi frequencies of the coupling field. Here, we investigate in detail the influence of the dephasing effect on the AIC weights of QI and ATS, and present the transition among destructive QI, constructive QI, and ATS without QI by controlling the dephasing rates. By comparing the effects of different dephasing rates on the QI and ATS weights, we show that the field-phase-diffusion dephasing provides more feasibility than the atom-collision dephasing in control of QI and ATS. Therefore, precise and selective dephasing engineering can be realized by manipulating the linewidths and phase correlation of the fields. This indicates that various collision-related effects (e.g., collision-dephasing-induced coherences) can be experimentally studied using more controllable field-phase-diffusion dephasing instead of buffer-gas-controlling collision dephasing.