Single photonic qutrit in a collective Rydberg polariton

TL;DR

This paper demonstrates the coherent creation, control, and read-out of a single photonic qutrit using a Rydberg ensemble, enabling fast quantum information processing and simulation with high-dimensional quantum states.

Contribution

It introduces a method to coherently manipulate a photonic qutrit via microwave-driven Rydberg states, achieving rapid control and read-out within microseconds.

Findings

Successful creation of a single photonic qutrit in a Rydberg ensemble

High-fidelity control and read-out within 1.8 microseconds

Good agreement between experimental results and theoretical models

Abstract

We report on the coherent creation, control and read-out of a single photonic qutrit in a Rydberg ensemble. In each measurement, an optical photon is stored as a Rydberg polariton through electromagnetically induced transparency. Employing two microwave fields, the polariton is driven into an arbitrary superposition of three collective states, each encoded in a Rydberg state. The collective state is mapped into a photonic time-bin qutrit with the microwave field and read out sequentially. The complete sequence, including preparation, control, and read-out, is less than 1.8~$\mu$s, which mitigates decoherence significantly. We measure the coherence of the qutrit with non-destructive Ramsey interferometry, which is preferable for quantum information processing, and find good quantitative agreement with the theoretical model. The ability to write, process and read out the single photonic qutrit on microsecond time scales with microwave coupled Rydberg states demonstrates the coherent connectivity among the high Hilbert space of the qutrit.Our study is an important step in exploring qutrit based quantum information processes and quantum simulation of topological physics with microwave coupled Rydberg atom ensembles.