Effects of ultrafast molecular rotation on collisional decoherence

TL;DR

This study investigates how ultrafast control of molecular rotation affects collisional decoherence in nitrogen molecules, revealing a significant change in decoherence rates across a broad range of rotational states.

Contribution

It introduces a method to control and study molecular rotation at high angular momenta, uncovering the crossover between adiabatic and non-adiabatic relaxation regimes.

Findings

Decoherence rate varies by over an order of magnitude across J=8 to J=66.

A simplified scaling law describes the dependence of decoherence on rotational quantum number J.

Demonstrates the ability to access and analyze regimes not reachable by thermal means.

Abstract

Using an optical centrifuge to control molecular rotation in an extremely broad range of angular momenta, we study coherent rotational dynamics of nitrogen molecules in the presence of collisions. We cover the range of rotational quantum numbers between J=8 and J=66 at room temperature and study a cross-over between the adiabatic and non-adiabatic regimes of rotational relaxation, which cannot be easily accessed by thermal means. We demonstrate that the rate of rotational decoherence changes by more than an order of magnitude in this range of J values, and show that its dependence on J can be described by a simplified scaling law.