Continuous Variable Quantum Random Number Generator: Security Analysis, Chip-Based Implementation and Experimental Verification

Quantum Cryptography offers already today first commercial available future proof security solutions, which cannot be matched by their classical counterparts. To offer competitive solutions, one has to build practical devices with high speeds and small form factors. Further, it is going to be of critical importance to implement new security standards, which ensure that new products can be tested to meet this new class of high-security claims.

A significant challenge is to close the gap between security proofs based on ideal devices and real-world implementations. Quantum random number generators require a high level of scrutiny since they are and an essential building used in a vast range of protocols. This work investigates the feasibility of building a high security continuous variable vacuum fluctuation QRNG on an integrated photonic platform.

In this work, one implements a QRNG based on a photonic chip with photodiodes connected by a beamsplitter in a homodyne configuration. Further, a solution with a chip-integrated local oscillator was studied. In order for the QRNG to be considered to be secure, it has to meet requirements as stated by a security proof.

On the other hand, one needs security proofs stating realizable device requirements. In this work, the security analysis for continuous variable QRNG was extended to take correlation into account. Further, one shows that these devices are also secure against a quantum capable adversary. This work studies the experimental verification method used to verify such continuous variable QRNG.

A new verification method is proposed in order to increase the security standard further.