Photon Antibunching in the Photoluminescence Spectra of a Single Carbon Nanotube

TL;DR

This paper reports the first observation of photon antibunching in single carbon nanotubes, demonstrating their potential as single-photon sources for quantum cryptography due to low multiphoton emission probability.

Contribution

It provides the first experimental evidence of photon antibunching in single carbon nanotubes and explores mechanisms like Auger processes and exciton localization affecting emission.

Findings

Photon antibunching observed in single nanotubes

Multiphoton emission probability below 5%

Implications for quantum cryptography applications

Abstract

We report the first observation of photon antibunching in the photoluminescence from single carbon nanotubes. The emergence of a fast luminescence decay component under strong optical excitation indicates that Auger processes are partially responsible for inhibiting two-photon generation. Additionally, the presence of exciton localization at low temperatures ensures that nanotubes emit photons predominantly one by one. The fact that multiphoton emission probability can be smaller than 5% suggests that carbon nanotubes could be used as a source of single photons for applications in quantum cryptography.