Broadband Modulation of Light by Coherent Molecular Oscillations

Joshua J. Weber, David Gold, Deniz D. Yavuz

E. Garmire, F. Pandarese, Charles Hard Townes

Alexei V. Sokolov, Mariia Shutova, Alexandra A. Zhdanova

We utilize laser-driven molecular oscillations to modulate light and produce a broadband spectrum of mutually coherent Ramansidebands, aiming toward synthesis of ultrafast optical waveforms with prescribed temporal and spatial shapes.

Joshua J. Weber, Jonathan Tyler Green, Deniz D. Yavuz

Roy Elbaz, Yaakov Yudkin, Panagiotis Giannakeas +3 more

We report the observation of coherent oscillations in conversion efficiency of weakly-bound dimers formed from a thermal gas of ultracold atoms. Finite thermal energy of the gas causes loss of coherence when a broad continuum is resonantly coupled to a discrete bound state. Restoration of the coherence can be achieved through non-adiabatic transitions of the dressed molecular energy level that are induced by a strong modulation pulse with fast envelope dynamics. Conditions to observe coherent oscillations are verified, and control of their properties is demonstrated. The main experimental findings are supported by theoretical modeling and numerical calculations. The observed results may lead to a renewed interest in general studies of a discrete energy level coupled to a broadband continuum when the properties of both are fully controlled.

Penghong Yu, Xiaoxiong Wu, Zhaohui Dong +5 more

We study the light evolution through a Raman-active medium, where a pair of fields pump molecules near-resonantly and excite the molecular coherence. A synthetic lattice including multiple frequency sidebands via the coherent Raman process is constructed. By varying the density of molecules in the light propagation direction, the system can present a lattice model undergoing dynamic modulations. Further considering the frequency-dependent couplings between synthetic lattice sites, we explore intriguing phenomena, including spectral Bloch oscillation and super Bloch oscillation with asymmetric patterns, which leads to interesting frequency-conversion phenomena with the Raman sideband generations. Our work could be useful for future experiments in coherent Raman sideband processes towards ultrashort pulse generations and higher-frequency conversion.