Decelerating molecules with microwave fields

TL;DR

This paper demonstrates an experimental microwave decelerator for neutral polar molecules, enabling control over their velocity and focusing, which advances molecular manipulation techniques.

Contribution

The authors developed and experimentally validated a microwave-based decelerator for high-field-seeking molecules, a novel approach in molecular beam control.

Findings

Successfully decelerated molecules from 20.0 m/s to 16.9 m/s

Guided and focused ammonia molecules in a microwave cavity

Achieved both deceleration and acceleration of molecular beams

Abstract

We here report on the experimental realization of a microwave decelerator for neutral polar molecules, suitable for decelerating and focusing molecules in high-field-seeking states. The multi-stage decelerator consists of a cylindrical microwave cavity oscillating on the TE 11n mode, with n=12 electric field maxima along the symmetry axis. By switching the microwave field on and off at the appropriate times, a beam of state-selected ammonia molecules with an incident mean velocity of 25 m/s is guided while being spatially focussed in the transverse direction and bunched in the forward direction. Deceleration from 20.0 m/s to 16.9 m/s and acceleration from 20.0 m/s to 22.7 m/s is demonstrated.