Franck-Condon tuning of optical cycling centers by organic functionalization

TL;DR

This paper explores how organic functionalization of alkaline earth phenoxides can optimize optical cycling transitions for quantum applications, showing that chemical modifications can reduce cycle leakage and enhance laser cooling potential.

Contribution

It introduces a theoretical approach to tuning optical cycling centers in organic compounds via chemical functionalization, expanding atomic techniques to organic molecules.

Findings

Low optical cycle leakage in phenoxides and derivatives

Chemical substitution enhances electron withdrawing effects

Functionalization improves suitability for laser cooling and quantum measurement

Abstract

Laser induced electronic excitations that spontaneously emit photons and decay directly to the initial ground state ("optical cycling transitions") are used in quantum information and precision measurement for state initialization and readout. To extend this primarily atomic technique to organic compounds, we theoretically investigate optical cycling of alkaline earth phenoxides and their functionalized derivatives. We find that optical cycle leakage due to wavefunction mismatch is low in these species, and can be further suppressed by using chemical substitution to boost the electron withdrawing strength of the aromatic molecular ligand through resonance and induction effects. This provides a straightforward way to use chemical functional groups to construct optical cycling moieties for laser cooling, state preparation, and quantum measurement.