Quantum modulation of a coherent state wavepacket with a single electron spin

TL;DR

This paper demonstrates a novel quantum interaction where a quantum dot's spin state dynamically modulates the phase of a coherent photon wavepacket, creating a new non-classical quantum state of light.

Contribution

It introduces a new type of spin-photon interaction involving dynamic modulation of a wavepacket by a quantum dot's spin, expanding the understanding of quantum light-matter interactions.

Findings

Quantum modulation of wavepacket phase (0 or π) achieved.

Demonstration of a non-classical quantum state of light.

New dynamic spin-photon interaction mechanism established.

Abstract

The interaction of quantum objects lies at the heart of fundamental quantum physics and is key to a wide range of quantum information technologies. Photon-quantum-emitter interactions are among the most widely studied. Two-qubit interactions are generally simplified into two quantum objects in static well-defined states . In this work we explore a fundamentally new dynamic type of spin-photon interaction. We demonstrate modulation of a coherent narrowband wavepacket with another truly quantum object, a quantum dot with ground state spin degree of freedom. What results is a quantum modulation of the wavepacket phase (either 0 or {\pi} but no values in between), a new quantum state of light that cannot be described classically.