Experimental Studies of the Transient Autler-Townes Effect.

Yan Bai, THOMAS W. MOSSBERG, Ning Lü +1 more

Claude N. Cohen-Tannoudji

Michael Chini, Xiaowei Wang, Yan Cheng +1 more

We present theoretical simulations of the attosecond transient absorption of singly-excited states of helium atoms in the presence of a dressing near-infrared or infrared laser. In particular, we aim to address several unresolved questions in the transient absorption of helium and to resolve the remaining discrepancies between theory and experiment. We initially focus on the forklike structures in the Autler–Townes splitting of the 1s2p state and the effects of resonant coupling to the 1s2s and 1s3s states. We find that the delay-dependent features of the Autler–Townes doublet depend strongly on both the laser frequency detuning from resonance and on the laser pulse duration, and explain the lack of such structures in current experimental data. Next, we identify the interference mechanism which causes the half-cycle oscillations in the absorption spectrum below the excited state manifold. Finally, we observe for the first time the presence of quantum beating in the simulated transient absorption spectrogram, and discuss the conditions under which such wavepacket dynamics could be observed experimentally.

Jingliang Liu, Hujiang Yang, Chuan Xi Wang +2 more

Here we experimentally demonstrated the electromagnetically induced transparency (EIT) and Autler-Townes splitting (ATS) effects in mechanical coupled pendulums. The analogue of EIT and ATS has been studied in mechanical systems and the intrinsic physics between these two phenomena are also been discussed. Exploiting the Akaike Information Criterion, we discern the ATS effect from EIT effect in our experimental results.

Yue Bai, THOMAS W. MOSSBERG, Ning Lü +1 more

Working with a beam of $^{174}\mathrm{Yb}$, we have studied the temporal development of Autler-Townes spectra following switchon of a strong, resonant, driving field. The transient fluorescence spectra observed are dramatically different from those found in the steady state. We find that either member of the Autler-Townes doublet can be eliminated by an appropriate shift in the phase of the driving field, and that the spectral peaks can display interesting temporal oscillations. The observed behavior is interpreted in terms of atomic dynamics and a polarization of the dressed atom-field states.

Ergin H. Ahmed, Xinhua Pan, Marjatta Lyyra