Abstract
Quantum correlations between long-lived quantum memories and telecom photons that can propagate with low loss in optical fibers are an essential resource for the realization of large-scale quantum information networks. Significant progress has been realized in this direction with atomic and solid-state systems. Here, we demonstrate quantum correlations between a telecom photon and a multimode on-demand solid state quantum memory. This is achieved by mapping a correlated single photon onto a spin collective excitation in a crystal for a controllable time. The stored single photons are generated by cavity-enhanced spontaneous parametric down-conversion and heralded by their partner photons at telecom wavelength. These results represent the first demonstration of a multimode on-demand solid state quantum memory for external quantum states of light. They provide an important resource for quantum repeaters and pave the way for the implementation of quantum information networks with distant solid state quantum nodes.
- Received 9 December 2016
DOI:https://doi.org/10.1103/PhysRevX.7.021028
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.
Published by the American Physical Society
Physics Subject Headings (PhySH)
Viewpoint
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Published 24 May 2017
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Popular Summary
Quantum communication networks offer the potential for highly secure transmission of sensitive information. Whereas traditional telecommunication devices manipulate voltages to transmit information in a series of 1s and 0s, quantum networks leverage the ability of photons and atoms to be in multiples states at once as well as linked (or “correlated”) over very large distances. Correlations between telecom photons and long-lived quantum memories are crucial for the development of architectures that are compatible with existing fiber-optic networks. We have developed a solid-state device, which promises scalability and integration with current systems. With this device, we show correlations between a telecom photon and a temporally multiplexed quantum memory.
We map a correlated single photon onto a spin-collective excitation in a rare-earth ion-doped crystal for a controllable time. The spin-collective excitation can be read out on demand, maintaining the quantum nature of the correlation. Moreover, the storage protocol allows for storing of multiple temporal modes, which is a fundamental benefit for enhancing the distribution rate of quantum information over long distances.
Our work demonstrates the first realization of a multimode solid-state quantum memory for single photons with on-demand readout, a significant advance in the field of photonic quantum memories. It is also a milestone experiment in quantum information science, as it enables the development of a quantum repeater architecture based on photon-pair sources and multimode quantum memories that are compatible with the existing fiber telecommunication network.