A designed concatenation of error correction protocols can yield an architecture for continuous-variable quantum repeaters. The idea relies on combining teleportation and entanglement distillation through noiseless linear amplification.

Abstract The no-cloning theorem states that an unknown quantum state cannot be cloned exactly and deterministically due to the linearity of mechanics. Associated with this is quantitative limit sets upper bound quality generated clones. However, can circumvented by abandoning determinism using probabilistic methods. Here, we report experimental demonstration cloning arbitrary coherent clearly surpasses limit. Our scheme based on a hybrid linear amplifier combines ideal deterministic heralded...

Quantum repeaters have been proposed as a way of extending the reach quantum communication. First generation approaches use entanglement swapping to connect entangled links along long distance channel. Recently, there proposals for first continuous variables. In this paper, we present an improved variable repeater scheme using optimal Gaussian swapping. Our uses noiseless linear amplifier distillation. We show that with simplest configuration and under assumption good memories perfect...

Entanglement distribution is crucial for quantum communication and cryptography but hindered by channel loss decoherence. Noiseless linear amplification (NLA) a probabilistic protocol that supports noiseless without violating the no-cloning theorem, aiding in tasks like entanglement distillation enhanced metrology. The nature of NLA other repeater elements creates significant resource overhead, which depends on success rate each individual step. We experimentally demonstrate technique to...

Principles of quantum mechanics promise a future internet that connects wide variety devices together in coherent and secure fashion. It is well known due to the size this internet, repeaters will be critical part similar fashion importance today's telecommunications internet. Given inherent differences between classical physics, it essential establish how function including we route information as functionality need provide. Our considerations here go far beyond key distribution instead...

Gaussian channels are the typical way to model decoherence introduced by environment in continuous-variable quantum states. It is known that those can be simulated a teleportation protocol using as resource state either maximally entangled passing through same channel, i.e., Choi state, or at least much state. Since construction of requires infinite mean energy and entanglement, it unphysical, we derive instead every physical able simulate given channel with finite resources further find...

Gaussian noise induced by loss on states may be corrected distributing Einstein-Podolsky-Rosen entanglement through the channel, purifying using a noiseless linear amplifier (NLA), and then it for continuous-variable teleportation of input state. Linear optical implementations NLA unavoidably introduce small amounts excess detection, source efficiency will limited in current implementations. In this paper, we analyze error-correction protocol with nonunit sources detectors show partially...

Quantum repeaters are used to overcome the exponential photon loss scaling that quantum states acquire as they transmitted over long distances. While for discrete-variable encodings of information have existed some time, approaches continuous-variable encoding only recently been proposed. In this work, we present a method using repeater protocol distribute and utilize it compare rates entanglement distribution between first-generation continuous- repeaters. Such comparison allows us begin...

Due to the pervasive nature of decoherence, protection quantum information during transmission is critical importance for any network. A linear amplifier that can enhance signals stronger than their associated noise while preserving coherence therefore great use. This seemingly unphysical property achievable a class probabilistic amplifiers does not work deterministically. Here we present amplification scheme realises this coherent states by combining heralded measurement-based noiseless and...

The generation and preservation of entanglement is a central goal in quantum technology. Traditionally, dissipation systems thought to be detrimental entanglement, however can also utilized as means generating between spins that are not directly interacting. In particular, generated two qubits, or multiqubit via collective coupling reservoir. this work, we explore multiple spin domains pairwise coupled different reservoirs show which each other, even the same

The transfer of energy through a network nodes is fundamental to both how nature and current technology operates. Traditionally we think the in being coupled channels that connect them then passed from node channel until it reaches its targeted site. Here introduce an alternate approach this where our are replaced by collective environments (or actually reservoirs) which interact with pairs nodes. We show initially located at specific can arrive target - even though environment may be zero...

Abstract Quantum error correction codes based on continuous variables play an important role for the implementation of quantum communication systems. A natural application such occurs within repeater systems which are used to combat severe channel losses and local gate errors. In particular, loss drastically reduces distance between remote users. Here, a cavity‐quantum electrodynamics (QED) scheme is considered address in channel. This relies transmission specific class rotationally...

We present quantum repeater networks utilizing rotation-symmetric bosonic codes to enhance the performance of long-distance communication. By adding multiple channels, it can be further improved and requirements are within state-of-art technology.

We explore a protocol that efficiently charges multiple open quantum batteries in parallel using single charger. This shows super-extensive charging through collective coupling of the charger and battery to same thermal reservoir. When applied batteries, each coupled different reservoirs, energy cannot be transferred from via dissipation alone. show counter-intuitive act incorporating both incoherent pumping on enables efficient many batteries.

We propose a quantum repeater for continuous variable (CV) optical states. Our relies on an error correction protocol loss CV states based teleportation and entanglement distillation via noiseless linear amplification. The is concatenated to preserve the same effective transmission coefficient channel over increasing distance. probability of successful operation scales polynomially with However, limited by trade-off between fidelity success.

The generation and preservation of entanglement is a central goal in quantum technology. Traditionally, dissipation systems thought to be detrimental entanglement, however can also utilised as means generating between spins that are not directly interacting. In particular generated two qubits, or multi qubit via collective coupling reservoir. this work, we explore multiple spin domains pairwise coupled different reservoirs show which each other, even the same

Quantum error correction codes based on continuous variables play an important role for the implementation of quantum communication systems. A natural application such occurs within repeater systems which are used to combat severe channel losses and local gate errors. In particular, loss drastically reduces distance between remote users. Here we consider a cavity-QED scheme address in channel. This relies transmission specific class rotationally invariant error-correcting codes. We compare...

The no-cloning theorem states that an unknown quantum state cannot be cloned exactly and deterministically. However, this limit can circumvented by abandoning determinism using probabilistic methods. Here, we report experimental demonstration of cloning arbitrary coherent clearly surpasses the limit. Our scheme is based on a hybrid linear amplifier combines ideal deterministic with heralded measurement-based noiseless amplifier. We demonstrate production up to five clones fidelity each clone...

We present an experimental enhancement of signal-to-noise ratio for arbitrary coherent states using a noise-reduced linear amplifier that profitably combines heralded measurement-based noiseless and deterministic amplifier. The concatenation two amplifiers introduces the flexibility allows one to reach amplification with high gain large input amplitude. demonstrate signal transfer coefficient Ts = 2.55 ± 0.08 from output, achieved 10.54. When Gaussian statistics is retained, our obtained...

We present an experimental enhancement of signal-to-noise ratio for arbitrary coherent states using a noise-reduced linear amplifier that profitably combines heralded measurement-based noiseless and deterministic amplifier. The concatenation two amplifiers introduces the flexibility allows one to reach amplification with high gain large input amplitude. demonstrate signal transfer coefficient Ts = 2.55 ± 0.08 from output, achieved 10.54. When Gaussian statistics is retained, our obtained...

Quantum repeaters are used to overcome the exponential photon loss scaling that quantum states acquire as they transmitted over long distances. While for discrete variable encodings of information have existed some time, novel approaches continuous encoding only recently been proposed. In this work, we present a method using repeater protocol distribute and utilize it compare rates entanglement distribution between first generation repeaters. Such comparison allows us begin benchmark two...