High-dimensional quantum key distribution using orbital angular momentum of single photons from a colloidal quantum dot at room temperature

Understand

High-dimensional quantum key distribution (HDQKD) is a promising avenue to address the inherent limitations of basic QKD protocols.

• However, experimental realizations of HDQKD to date have relied on indeterministic photon sources that limit the achievable key rate.
• In this paper, we demonstrate a full emulation of a HDQKD system using a single colloidal giant quantum dot (gQD) as a deterministic, compact and room-temperature single-photon source (SPS).
• We demonstrate a practical protocol by encoding information in a high-dimensional space ($d = 3$) of the orbital angular momentum of the photons.