Continuously tunable single-photon level nonlinearity with Rydberg state wave-function engineering

TL;DR

This paper demonstrates a method to achieve continuously tunable single-photon level nonlinearity using Rydberg state wave-function engineering, enabling faster quantum state preparation and advancing scalable quantum information processing.

Contribution

It introduces microwave-assisted wave-function engineering to control Rydberg interactions over two orders of magnitude for tunable optical nonlinearity at the single-photon level.

Findings

Achieved continuous tunability of Rydberg-mediated nonlinearity.

Demonstrated a 40-fold speed-up in preparing Rydberg single-photon states.

Showed potential for improved quantum operations in Rydberg systems.

Abstract

Extending optical nonlinearity into the extremely weak light regime is at the heart of quantum optics, since it enables the efficient generation of photonic entanglement and implementation of photonic quantum logic gate. Here, we demonstrate the capability for continuously tunable single-photon level nonlinearity, enabled by precise control of Rydberg interaction over two orders of magnitude, through the use of microwave-assisted wave-function engineering. To characterize this nonlinearity, light storage and retrieval protocol utilizing Rydberg electromagnetically induced transparency is employed, and the quantum statistics of the retrieved photons are analyzed. As a first application, we demonstrate our protocol can speed up the preparation of single photons in low-lying Rydberg states by a factor of up to ~ 40. Our work holds the potential to accelerate quantum operations and to improve the circuit depth and connectivity in Rydberg systems, representing a crucial step towards scalable quantum information processing with Rydberg atoms.