Storage of light: A useful concept?

Robust Quantum Entanglement Generation and Generation-plus-Storage Protocols with Spin Chains

Reliable quantum communication/processing links between modules are a necessary building block for various quantum processing architectures. Here we consider a spin chain system with alternating strength couplings and containing three defects, that impose three domain walls between topologically distinct regions of the chain. We show that -- in addition to its useful, high fidelity, quantum state transfer properties -- an entangling protocol can be implemented in this system, with optional localisation and storage of the entangled states. We demonstrate both numerically and analytically that, …

Informational work storage in quantum thermodynamics

We present a critical examination of the difficulties with the quantum versions of a lifted weight that are widely used as work storage systems in quantum thermodynamics. To overcome those difficulties, we turn to the strong connections between information and thermodynamics illuminated by Szilard's engine and Landauer's principle, and consider the concept of informational work storage. This concept is in sharp contrast with the usual one of mechanical work storage underlying the idealization of a quantum weight. An informational work storage system based on maximally mixed qubits that does no…

连续变量量子电池中的非线性耦合能量存储

Energy storage in a continuous-variable quantum battery with nonlinear coupling

研究连续变量量子电池中最大可提取能量与海森堡不确定性原理的关系，发现最小不确定性可保证高斯量子电池能量全部可提取，并通过量子压缩在非线性耦合中非平凡实现，为设计高效玻色子量子电池提供理论依据。

Temporal multimode storage of entangled photon pairs

Multiplexed quantum memories capable of storing and processing entangled photons are essential for the development of quantum networks. In this context, we demonstrate the simultaneous storage and retrieval of two entangled photons inside a solid-state quantum memory and measure a temporal multimode capacity of ten modes. This is achieved by producing two polarization entangled pairs from parametric down conversion and mapping one photon of each pair onto a rare-earth-ion doped (REID) crystal using the atomic frequency comb (AFC) protocol. We develop a concept of indirect entanglement witnesse…

迈向高效4能级光子回波存储器的进展

Progress towards efficient 4-level photon echo memories

本研究在Er:YSO中使用4能级重相位放大自发辐射协议实现了高效自旋存储量子存储器，召回效率达80%，支持70个时间模式存储，并展示了ASE和RASE场间的非经典相关性，为量子网络和量子计算应用提供了明确改进路径。

Controlled transport of stored light

Controlled manipulation, storage and retrieval of quantum information is essential for quantum communication and computing. Quantum memories for light, realized with cold atomic samples as the storage medium, are prominent for their high storage efficiencies and lifetime. We demonstrate the controlled transport of stored light over 1:2 mm in such a storage system and show that the transport process and its dynamics only have a minor effect on the coherence of the storage. Extending the presented concept to longer transport distances and augmenting the number of storage sections will allow for …