Deterministic implementation of weak quantum cubic nonlinearity

TL;DR

This paper presents a method for deterministically implementing weak quantum cubic nonlinearity, a key component for continuous-variable quantum computing, using ancillary states, Gaussian operations, and feed-forward, feasible with current technology.

Contribution

It introduces a novel deterministic approach to realize weak quantum cubic nonlinearity, advancing the development of continuous-variable quantum computation.

Findings

Implementation is feasible with current technology.

Nonlinear properties transferred via Gaussian operations and feed-forward.

Verification of nonlinearity achievable despite imperfections.

Abstract

We propose a deterministic implementation of weak cubic nonlinearity, which is a basic building block of a full scale CV quantum computation. Our proposal relies on preparation of a specific ancillary state and transferring its nonlinear properties onto the desired target by means of deterministic Gaussian operations and feed-forward. We show that, despite the imperfections arising from the deterministic nature of the operation, the weak quantum nonlinearity can be implemented and verified with the current level of technology.