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Related papers: Optimization approach to entanglement distillation

200 papers

In this paper, we present a general numerical framework for both deterministic and probabilistic quantum state transformations, under locality constraints. For a given arbitrary bipartite initial state and a desired bipartite target state,…

Quantum Physics · Physics 2025-12-25 Sasan Sarbishegi , Maryam Sadat Mirkamali

Knowledge distillation has emerged as an effective strategy for compressing large language models' (LLMs) knowledge into smaller, more efficient student models. However, standard one-shot distillation methods often produce suboptimal…

Computation and Language · Computer Science 2025-04-04 Kushal Jain , Piyushi Goyal , Kumar Shridhar

Uncontrolled interactions with the environment introduce errors that remain a significant challenge to the reliability of quantum technologies using entanglement. An essential method to overcome or mitigate these errors is entanglement…

Quantum Physics · Physics 2025-08-05 Christopher Popp , Tobias C. Sutter , Beatrix C. Hiesmayr

We propose a scheme for distillation of free bipartite entanglement from bipartite bound-entangled states. The crucial element of our scheme is an ancillary system that is coupled to the initial bound-entangled state via appropriate weak…

Quantum Physics · Physics 2013-12-19 S. Baghbanzadeh , A. T. Rezakhani

We characterize the multipartite entanglement of a system of n qubits in terms of the distribution function of the bipartite purity over balanced bipartitions. We search for maximally multipartite entangled states, whose average purity is…

Quantum Physics · Physics 2015-03-13 P. Facchi , G. Florio , U. Marzolino , G. Parisi , S. Pascazio

Quantum technologies rely on high-quality resource states, such as maximally entangled or private states, which are indispensable for quantum communication and cryptography. In practice, however, these states are inevitably degraded by…

Quantum Physics · Physics 2026-03-05 Christopher Popp , Tobias C. Sutter , Beatrix C. Hiesmayr

Optimal control theory is a versatile tool that presents a route to significantly improving figures of merit for quantum information tasks. We combine it here with the geometric theory for local equivalence classes of two-qubit operations…

Quantum Physics · Physics 2015-03-19 M. M. Müller , D. M. Reich , M. Murphy , H. Yuan , J. Vala , K. B. Whaley , T. Calarco , C. P. Koch

We investigate efficient entanglement purification through double selection process. This method works with higher noise thresholds for the communication channels and local operations, and achieves higher fidelity of purified states.…

Quantum Physics · Physics 2015-05-13 Keisuke Fujii , Katsuji Yamamoto

An experimental scheme for concentrating entanglement in partially entangled photon pairs is proposed. In this scheme, two separated parties obtain one maximally entangled photon pair from previously shared two partially entangled photon…

Quantum Physics · Physics 2009-11-07 Takashi Yamamoto , Masato Koashi , Nobuyuki Imoto

We show the enhancement of distillable key rate for quantum key distribution(QKD), by local filtering, for several bound entangled states. Through our work it becomes evident that the local filtration operations, while transforming one…

Quantum Physics · Physics 2020-09-24 Mayank Mishra , Ritabrata Sengupta , Arvind

In this paper, we proposed a physical scheme to concentrate the non-maximally entangled atomic pure states via cavity QED by using atomic collision in a far-off-resonant cavity. The most distinctive advantage of our scheme is that there is…

Quantum Physics · Physics 2009-11-10 Zhuo-Liang Cao , Ming Yang

The distribution of entangled states between distant parties in an optical network is crucial for the successful implementation of various quantum communication protocols such as quantum cryptography, teleportation and dense coding [1-3].…

Output entanglement is a key element in quantum information processing. Here, we show how to obtain optimal entanglement between two filtered output fields in a three-mode optomechanical system. First, we obtain the key analytical…

Quantum Physics · Physics 2019-08-14 Xiao-Bo Yan , Zhi-Jiao Deng , Xue-Dong Tian , Jin-Hui Wu

We present a detailed theoretical analysis for the distillation of one copy of a mixed two-mode continuous-variable entangled state using beamsplitters and coherent photon-detection techniques, including conventional on-off detectors and…

Quantum Physics · Physics 2013-05-29 ShengLi Zhang , Peter van Loock

Adiabatic passage of two correlated electrons in three coupled quantum dots is shown to provide a robust and controlled way of distilling, transporting and detecting spin entanglement, as well as of measuring the rate of spin…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Jaroslav Fabian , Ulrich Hohenester

Estimating noise processes is an essential step for practical quantum information processing. Standard estimation tools require consuming valuable quantum resources. Here we ask the question of whether the noise affecting entangled states…

We address the problem of discriminating with minimal error probability two given quantum operations. We show that the use of entangled input states generally improves the discrimination. For Pauli channels we provide a complete comparison…

Quantum Physics · Physics 2009-11-11 Massimiliano F. Sacchi

We introduce a class of quantum channels with correlations acting on pairs of qubits, where the correlation takes the form of a shift operator onto a maximally entangled state. We optimise the output purity and show that below a certain…

Quantum Physics · Physics 2008-05-19 Filippo Caruso , Vittorio Giovannetti , Chiara Macchiavello , Mary Beth Ruskai

Entanglement among a large number of qubits is a crucial resource for many quantum algorithms. Such many-body states have been efficiently generated by entangling a chain of itinerant photonic qubits in the optical or microwave domain.…

We consider entanglement distillation from a single-copy of a multipartite state, and instead of rates we analyze the "quality" of the distilled entanglement. This "quality" is quantified by the fidelity with the GHZ-state. We show that…

Quantum Physics · Physics 2009-11-11 Ll. Masanes