# A Broadband DLCZ Quantum Memory in Room-Temperature Atoms

## TL;DR

This paper demonstrates a room-temperature broadband quantum memory using the FORD protocol in atoms, achieving low noise and high quantum correlation, paving the way for scalable quantum technologies at ambient conditions.

## Contribution

It introduces a novel room-temperature broadband quantum memory with high fidelity and low noise, surpassing previous limitations and enabling practical quantum applications.

## Key findings

- Low unconditional noise level of 10^{-4}
- Cross-correlation up to 28 indicating strong quantum correlation
- Violation of Bell's inequality at room temperature

## Abstract

Quantum memory capable of stopping flying photons and storing their quantum coherence is essential for scalable quantum technologies. A room-temperature broadband quantum memory will enable the implementation of large-scale quantum systems for real-life applications. Due to either intrinsic high noises or short lifetime, it is still challenging to find a room-temperature broadband quantum memory beyond conceptual demonstration. Here, we present a far-off-resonance Duan-Lukin-Cirac-Zoller (FORD) protocol and demonstrate the broadband quantum memory in room-temperature atoms. We observe a low unconditional noise level of $10^{-4}$ and a cross-correlation up to 28. A strong violation of Cauchy-Schwarz inequality indicates high-fidelity generation and preservation of non-classical correlation. Furthermore, the achieved cross-correlation in room-temperature atoms exceeds the key boundary of 6 above which quantum correlation is able to violate Bell's inequality. Our results open up the door to an entirely new realm of memory-enabled quantum applications at ambient conditions.