An On-chip Homodyne Detector for Measuring Quantum States and Generating Random Numbers

TL;DR

This paper introduces the first fully integrated silicon photonics homodyne detector capable of high-speed quantum state measurement and random number generation, advancing on-chip quantum optics technology.

Contribution

It presents a novel on-chip homodyne detector with high speed and low noise, enabling quantum state characterization and fast quantum random number generation.

Findings

Achieved 160 MHz measurement speed with 10 dB shot noise clearance.

Generated quantum random numbers at 1.2 Gbps passing NIST tests.

Demonstrated on-chip measurement of quantum states like Fock and squeezed states.

Abstract

Optical homodyne detection has found use in a range of quantum technologies as both a characterisation tool and as a way to post-selectively generate non-linearities. So far optical implementations have been limited to bulk optics. Here we present the first homodyne detector fully integrated with silicon photonics and suitable for measurements of the quantum state of the electromagnetic field. This high speed, compact detector shows low noise operation, with 10 dB of clearance between shot noise and electronic noise, up to a speed of 160 MHz. These performances are suitable for on-chip characterisation of optical quantum states, such as Fock or squeezed states. As a first application, we show the generation of quantum random numbers at 1.2 Gbps generation rate. The produced random numbers pass all the statistical tests provided by the NIST statistical test suite.