Single photon emission from graphene quantum dots at room temperature

TL;DR

This paper demonstrates that graphene quantum dots can emit single photons at room temperature with high purity, brightness, and stability, opening new avenues for quantum technology applications.

Contribution

It provides the first direct study of a single graphene quantum dot's intrinsic properties, highlighting its potential as a quantum emitter.

Findings

Single graphene quantum dots emit single photons at room temperature.

High purity, brightness, and photostability of the emission.

Potential for developing new quantum systems based on graphene nanoscale pieces.

Abstract

In the field of condensed matter, graphene plays a central role as an emerging material for nanoelectronics. Nevertheless, graphene is a semimetal, which constitutes a severe limitation for some future applications. Therefore, a lot of efforts are being made to develop semiconductor materials whose structure is compatible with the graphene lattice. In this perspective, little pieces of graphene represent a promising alternative. In particular, their electronic, optical and spin properties can be in principle controlled by designing their size, shape and edges. As an example, graphene nanoribbons with zigzag edges have localized spin polarized states. Likewise, singlet-triplet energy splitting can be chosen by designing the structure of graphene quantum dots. Moreover, bottom-up molecular synthesis put these potentialities at our fingertips. Here, we report on a single emitter study that directly addresses the intrinsic properties of a single graphene quantum dot. In particular, we show that graphene quantum dots emit single photons at room temperature with a high purity, a high brightness and a good photostability. These results pave the way to the development of new quantum systems based on these nanoscale pieces of graphene.