Rotational control of asymmetric molecules: dipole- vs. polarizability- driven rotational dynamics

TL;DR

This study demonstrates how optical and terahertz fields can be used as distinct and complementary tools to control the rotational dynamics of asymmetric molecules, validated by experiments and simulations.

Contribution

It provides experimental evidence and simulation validation for using dipole and polarizability interactions as separate rotational control mechanisms in asymmetric molecules.

Findings

Distinct quantum revivals observed for dipole- and polarizability-driven dynamics

Excellent agreement between experiments and RPWF simulations

Verification of RPWF as an efficient method for molecular dynamics calculation

Abstract

We experimentally study the optical- and terahertz- induced rotational dynamics of asymmetric molecules in the gas phase. Terahertz and optical fields are identified as two distinct control handles over asymmetric molecules, as they couple to the rotational degrees of freedom via the molecular- dipole and polarizability selectively. The distinction between those two rotational handles is highlighted by different types of quantum revivals observed in long duration (>100ps) field-free rotational evolution. The experimental results are in excellent agreement with Random Phase Wave Function simulations [Phys. Rev. A 91, 063420 (2015)] and provide verification of the RPWF as an efficient method for calculating asymmetric molecular dynamics at ambient temperatures, where exact calculation methods are practically not feasible. Our observations and analysis pave the way for orchestrated excitations by both optical and THz fields as complementary rotational handles, that enable a plethora of new possibilities in three-dimensional rotational control of asymmetric molecules.