Photostop: Production of zero-velocity molecules by photodissociation in a molecular beam

TL;DR

Photostop is a novel technique that uses photodissociation to produce molecules with zero velocity in the lab frame, enabling high-density trapping of molecules like NO.

Contribution

This paper introduces photostop, a new, cost-effective method for creating high-density, zero-velocity molecules suitable for trapping and further manipulation.

Findings

Produced NO molecules with zero velocity distribution

Achieved molecular densities of 1E7 cm-3

Observed molecules at a temperature of 1.6 K

Abstract

We have demonstrated a new, accessible and economical technique, dubbed photostop, for producing high densities of trappable molecules. Direct measurements are presented of NO molecules produced with a narrow velocity distribution centered at zero in the laboratory frame. NO2, initially cooled in a pulsed molecular beam, is photodissociated such that the recoil velocity of the NO photofragments cancels out the velocity of the beam. NO(X^2Pi_3/2, v=0, J=1.5) molecules are observed up to 10 mircoseconds after the dissociation event in the probe volume at an estimated density of 1E7 cm-3 per quantum state and at a translational temperature of 1.6 K. Through the choice of suitable precursors, photostop has the potential to extend the list atoms and molecules that can be slowed or trapped. It should be possible to accumulate density in a trap through consecutive loading of multiple pulses.