Single photon randomness originating from the symmetry of dipole emission and the unpredictability of spontaneous emission

TL;DR

This paper demonstrates a novel quantum random number generator based on spontaneous emission and dipole symmetry in defect centers of hexagonal boron nitride, promising room-temperature quantum communication applications.

Contribution

It introduces a new method for quantum random number generation utilizing spontaneous emission and dipole symmetry, validated with defect centers in hexagonal boron nitride.

Findings

Randomness confirmed by NIST tests

Randomness persists across independent defect centers

Potential for room-temperature solid-state quantum communication

Abstract

Quantum random number generation is a key ingredient for quantum cryptography and fundamental quantum optics and could advance Monte-Carlo simulations and machine learning. An established generation scheme is based on single photons impinging on a beam splitter. Here, we experimentally demonstrate quantum random number generation solely based on the spontaneous emission process in combination with the symmetric emission profile of a dipole aligned orthogonal to the laboratory frame. The demonstration builds on defect centers in hexagonal boron nitride and benefits from the ability to manipulate and align the emission directionality. We prove the randomness in the correlated photon detection events making use of the NIST randomness test suite and show that the randomness remains for two independently emitting defect centers. The scheme can be extended to random number generation by coherent single photons with potential applications in solid-state based quantum communication at room temperature.