Orienting Asymmetric Molecules by Laser Fields with Twisted Polarization.

Area of Science:

• Physical Chemistry
• Quantum Optics
• Molecular Physics

Background:

• Asymmetric molecules, particularly chiral ones, exhibit unique interactions with electromagnetic fields.
• Laser-induced molecular orientation is a developing field with potential applications in spectroscopy and materials science.

Purpose of the Study:

• To investigate the interaction of asymmetric molecules with twisted polarization laser fields.
• To elucidate the mechanism of laser-induced molecular orientation and torque generation.
• To explore the potential of this phenomenon for chiral analysis.

Main Methods:

• Theoretical study of molecular dynamics under laser excitation.
• Simulation of interaction between asymmetric molecules and time-delayed, cross-polarized laser pulses.
• Analysis of induced molecular rotation, torque, and dipole moment oscillations.

Main Results:

• Unidirectional rotation of the most polarizable molecular axis.
• Induction of a directed torque, leading to transient molecular orientation.
• Out-of-phase dipole moment oscillations for different molecular enantiomers.
• Generation of microwave radiation from chiral molecular mixtures.

Conclusions:

• The laser-induced orientation of asymmetric molecules is a classical effect.
• Twisted polarization laser fields can control molecular orientation and rotation.
• The generated microwave radiation offers a novel method for chiral discrimination.