Single organic molecules for photonic quantum technologies

TL;DR

Single organic molecules in solid matrices at low temperatures serve as versatile quantum emitters with applications in quantum communication, sensing, and integrated photonic systems, offering coherence and scalability advantages.

Contribution

This paper reviews the potential of single organic molecules as quantum emitters and their integration into photonic technologies, highlighting recent advances and future prospects.

Findings

Molecules exhibit narrow transition lines limited by excited state lifetime

Controlled coupling to photonic structures enhances light-matter interaction

Molecules can serve as single-photon sources and quantum sensors

Abstract

Isolating single molecules in the solid state has allowed fundamental experiments in basic and applied sciences. When cooled down to liquid helium temperature, certain molecules show transition lines, that are tens of megahertz wide, limited only by the excited state lifetime. The extreme flexibility in the synthesis of organic materials provides, at low costs, a wide palette of emission wavelengths and supporting matrices for such single chromophores. In the last decades, the controlled coupling to photonic structures has led to an optimized interaction efficiency with light. Molecules can hence be operated as single photon sources and as non-linear elements with competitive performance in terms of coherence, scalability and compatibility with diverse integrated platforms. Moreover, they can be used as transducers for the optical read-out of fields and material properties, with the promise of single-quanta resolution in the sensing of charges and motion. We show that quantum emitters based on single molecules hold promise to play a key role in the development of quantum science and technologies.