Integrated optical quantum memory controlled by electro-optic effect

TL;DR

This paper proposes an integrated optical quantum memory using erbium-doped lithium niobate micro-cavities controlled by the electro-optic effect, enabling scalable quantum networks with high efficiency.

Contribution

It introduces a novel approach combining rare earth ions and lithium niobate for on-chip quantum memory with electro-optic control, enhancing scalability and controllability.

Findings

High efficiency and low noise performance demonstrated

Electro-optic control enables dynamic resonance tuning

Suppression and enhancement of photon echoes achieved

Abstract

Integrated optical quantum memories are a scalable solution to synchronize a large number of quantum nodes. Without compact quantum memories, some astonishing quantum applications such as distributed quantum computing and quantum sensor networks would not be possible. Rather than find a specific material that meets all the requirements of an on-chip quantum memory as other protocols usually do, we propose to assign the memory requirements on coherent storage and controllability to rare earth ions and a lithium niobate crystal, respectively. Specifically, optical quantum states are stored in an erbium-doped lithium niobate micro-cavity by utilizing the electro-optic effect of lithium niobate. The cavity frequency can be shifted by an external electric field, thus modifying the resonance condition between the cavity and the collective atomic excitation. This effect is further used to suppress or enhance the emission of photon echoes. Our calculated results show that high efficiency and low noise performance is achievable.