Complete quantum state selectivity in cold molecular beams using deflection-resistant dark states in a STIRAP configuration

TL;DR

This paper introduces a method to achieve complete quantum state selectivity in cold molecular beams by utilizing dark states in a STIRAP configuration, enabling precise control over molecular quantum states.

Contribution

The authors demonstrate a novel technique using dark states in a STIRAP setup to produce fully quantum state-selected molecular beams, resistant to deflection and tunable at will.

Findings

Achieved complete quantum state selectivity in cold molecular beams.

Demonstrated purification of thermal beams of LiRb and IF molecules.

Enabled creation of superpositions of quantum states.

Abstract

One of the main goals of chemical dynamics is the creation of molecular beams composed of a single (vibrational, rotational, and magnetic) quantum state of choice. In this paper we show that it is possible to achieve {\it complete} quantum state selectivity by producing resistance to electromagnetically induced deflection (EID) and that the state to be selected can be "dialed in" at will. We illustrate the method by showing in detail how to purify thermal beams of the LiRb and IF molecules to yield molecular beams composed of a variety of pre-chosen single internal quantum states and/or superpositions of such states. We expect that this method will be implemented in all subsequent explorations of the fundamentals of chemical reactions and their control, and the use of cold molecules as a vehicle for studying some of the most profound issues of quantum dynamics.