Quantum Information Processing最新文献

{"title":"An in-depth analysis of QKD channel and secret key rate in free space laser optics for next generation secure networks","authors":"Peppino Fazio,&nbsp;Mauro Tropea,&nbsp;Miralem Mehic,&nbsp;Floriano De Rango,&nbsp;Miroslav Voznak","doi":"10.1007/s11128-026-05323-w","DOIUrl":"10.1007/s11128-026-05323-w","url":null,"abstract":"<div><p>Free Space Optics (FSO) is a highly promising technology for secure, high-speed communication, offering a versatile and adaptable solution across various network architectures by leveraging the power of laser-based transmission. This study specifically focuses on terrestrial point-to-point laser communication, with an emphasis on key performance metrics such as Signal-to-Noise Ratio, Total System Efficiency, and Secret Key Rate. A systematic analysis is conducted across a variety of realistic operational scenarios to assess the feasibility of long-distance secure communication while maintaining acceptable performance. To establish a thorough understanding of the reachable performance, this research employs an extensive series of simulations. Various practical conditions are examined, considering the impact of key parameters such as data transmission rates, atmospheric visibility, link distance, and adaptive optics enhancements. The findings contribute to a detailed performance evaluation of terrestrial FSO links, offering valuable insights into their practical deployment and long-term viability as a secure communication technology.</p></div>","PeriodicalId":746,"journal":{"name":"Quantum Information Processing","volume":"25 10","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148986314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Weak-measurement assisted quantum teleportation fidelity enhancement under noise","authors":"Mohit Dhanik,&nbsp;Shraddha Sharma,&nbsp;Pitamber Mahanandia","doi":"10.1007/s11128-026-05318-7","DOIUrl":"10.1007/s11128-026-05318-7","url":null,"abstract":"<div><p>This study presents an improved quantum teleportation protocol designed to enhance fidelity in noisy environments by combining weak measurements (WMs) with flip and reversal operations. In our scheme, Alice prepares a four-qubit entangled state and shares one of the entangled qubits with Bob, which serves as the quantum channel for teleporting an arbitrary single-qubit state. Since the communication channel is subject to noise, Alice performs a weak measurement on the shared qubit before transmission to reduce the impact of decoherence. Building upon existing WM-flip-reversal frameworks, we propose a modified weak measurement and reversal (WMR) protocol tailored for different noises in a four-qubit entangled system. The approach applies WM and flip operations prior to transmission to enhance resilience against noise, followed by corresponding reversal operations after transmission to recover the original quantum state. We systematically compare the performance of our proposed WMR protocol with the previously proposed WM-flip-reversal method under three common noise models: amplitude damping channel (ADC), phase flip channel (PFC), and bit flip channel (BFC). Our analysis reveals that the modified WMR scheme achieves significantly higher teleportation fidelity and improved robustness, particularly in bit flip noise environments. These findings highlight the potential of optimized weak measurement strategies for developing more reliable and noise-tolerant quantum communication protocols.</p></div>","PeriodicalId":746,"journal":{"name":"Quantum Information Processing","volume":"25 10","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148986364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantum geometry and dynamics of two interacting spins: interplay with entanglement and quantum teleportation","authors":"Chaymae Boukacem,&nbsp;Mouhcine Yachi,&nbsp;Oussama Latifi,&nbsp;Brahim Amghar,&nbsp;Hamid Nebdi,&nbsp;Abdallah Slaoui","doi":"10.1007/s11128-026-05315-w","DOIUrl":"10.1007/s11128-026-05315-w","url":null,"abstract":"<div><p>We develop a unified geometric and dynamical description of a two-spin system governed by the isotropic XXX Heisenberg model, incorporating both the antisymmetric Dzyaloshinskii–Moriya (DM) interaction and an external magnetic field oriented along the <i>z</i>-axis. Within the Fubini–Study formalism, we derive the quantum metric tensor and show that the system evolves on a compact three-dimensional torus <span>(mathbb {T}^3)</span>, whose nontrivial topology provides a natural framework for describing the quantum evolution. We further show that, despite its toroidal topology, the associated quantum state manifold remains intrinsically flat. The geometric phase accumulated during the evolution reflects the global properties of the quantum state trajectory in the relevant quantum state space, thereby providing information beyond that contained in the dynamical phase. Entanglement, quantified through Wootters concurrence, is analyzed in connection with the geometric and dynamical properties of the system. By expressing the geometric phase, the Fubini–Study distance, and the evolution speed in terms of concurrence, we find that these quantities arise from the same underlying quantum evolution. In particular, increasing entanglement is accompanied by larger state-space distinguishability and faster quantum evolution, while the DM interaction modifies these behaviors through its influence on the quantum coherences of the spin system. Finally, by examining quantum teleportation through its relation to the geometric phase, the evolution speed, and the Fubini–Study distance, we demonstrate that high teleportation fidelities are associated with larger geometric phases, greater distinguishability between quantum states, and higher evolution speeds. This work provides a coherent framework linking geometry, entanglement, dynamics, and information transfer, highlighting the role of quantum state geometry in understanding quantum information tasks.\u0000</p></div>","PeriodicalId":746,"journal":{"name":"Quantum Information Processing","volume":"25 10","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dark-mode broadband quantum force sensing in a two-mode qubit-Kerr optomechanical system","authors":"F. Aljuaydi,&nbsp;H. Allhibi,&nbsp;E. K. Jaradat,&nbsp;M. Noman,&nbsp;A.-B. A. Mohamed","doi":"10.1007/s11128-026-05338-3","DOIUrl":"10.1007/s11128-026-05338-3","url":null,"abstract":"<div><p>Cavity-optomechanical force sensors can reach sensitivities below the standard quantum limit, but this advantage usually appears only within a narrow frequency range. Here, we propose a two-mode qubit-Kerr optomechanical sensor designed to broaden this useful sensing window. In the proposed setup, the unknown force acts on one mechanical resonator, while the optical cavity reads out the response through a second mechanically coupled resonator. A dispersively coupled qubit tunes the effective stiffness of the readout mode, and the Kerr cavity provides additional control over the detected optical quadrature. Near the mechanical matching condition, the two resonators form bright and dark supermodes, allowing the force signal to be transferred while part of the added noise is suppressed by interference. Using a full transfer-function analysis, we show that the sensor can either broaden the continuous sub-SQL bandwidth by a factor of 2.19, with a total bandwidth gain of 3.05, or reduce the minimum added force noise by about <span>(17.1~textrm{dB})</span> while retaining a finite bandwidth. Stability checks, thermal tests, and mechanism-ablation results confirm that the improvement comes from dark-mode transduction rather than a simple resonance shift. These results suggest a practical route towards broadband and low-noise hybrid quantum force sensing.\u0000</p></div>","PeriodicalId":746,"journal":{"name":"Quantum Information Processing","volume":"25 9","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction: Quantifying multi-qubit coherence","authors":"Shivang Pandey,&nbsp;Debabrata Goswami","doi":"10.1007/s11128-026-05319-6","DOIUrl":"10.1007/s11128-026-05319-6","url":null,"abstract":"","PeriodicalId":746,"journal":{"name":"Quantum Information Processing","volume":"25 9","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural perspectives from quantum states and measurements in optimal state discrimination","authors":"Hyunho Cha,&nbsp;Jungwoo Lee","doi":"10.1007/s11128-026-05335-6","DOIUrl":"10.1007/s11128-026-05335-6","url":null,"abstract":"<div><p>Quantum state discrimination refers to a class of techniques to identify a specific quantum state through a <i>positive operator-valued measure</i>. In this work, we investigate how structural information can influence our ability to determine or bound the optimal discrimination probability. First, as background, we note that for single-qubit pure-state ensembles, pairwise fidelities determine the optimal discrimination probability, whereas in higher dimensions they do not in general. As an illustrative application of this observation, we give a closed-form fidelity-based reformulation of the optimal discrimination probability for three equiprobable single-qubit states with equal pairwise fidelities. Secondly, we show that the information of measurement operators that vanish in the optimal solution can be used to refine upper bounds on the optimal discrimination probability, often yielding tighter bounds.</p></div>","PeriodicalId":746,"journal":{"name":"Quantum Information Processing","volume":"25 9","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11128-026-05335-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A provably secure framework for noise-aware delegated quantum computation and storage","authors":"Sanidhya Gupta,&nbsp;Ankur Raina","doi":"10.1007/s11128-026-05329-4","DOIUrl":"10.1007/s11128-026-05329-4","url":null,"abstract":"<div><p>As large-scale quantum computers become a reality, they will likely exist as centralized cloud resources accessible to a broad user base. Securely delegating private quantum computations to untrusted servers is therefore a foundational challenge. This requires rigorous guarantees of privacy (blindness), correctness (completeness), and integrity against malicious actions (verifiability). This paper presents an integrated architectural framework for noise-aware distributed quantum computation. The framework combines three technical components into a unified system: (1) a distributed stabilizer code backbone to encode and store quantum states across multiple server nodes, with security analyzed under non-communication and bounded collusion assumptions; (2) a two-level error management structure, where each server node can locally handle errors based on its specific noise model; and (3) a trap-based verification protocol to detect malicious deviations with probability controlled by a security parameter. We provide a security analysis showing that, under the stated assumptions, the framework achieves completeness, blindness, and verifiability with respect to the permitted leakage. Our work provides an architectural blueprint for trustworthy distributed quantum computation under explicitly stated assumptions, paving the way for further development of secure quantum cloud services.</p></div>","PeriodicalId":746,"journal":{"name":"Quantum Information Processing","volume":"25 9","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coherence-selective non-Markovian qubit dynamics","authors":"Ridha Horchani","doi":"10.1007/s11128-026-05336-5","DOIUrl":"10.1007/s11128-026-05336-5","url":null,"abstract":"<div><p>Structured pure dephasing can produce coherence revival, but a predictive reduced description must also identify the physically admissible parameter domain and connect observables obtained under different control protocols. We study a constrained memory kernel composed of a short-memory broadband term and a finite-linewidth damped-oscillatory term, the minimal background-plus-resonance member of a hierarchy for spectra dominated by one isolated finite-linewidth feature. Although their difference defines a single scalar Volterra kernel, independent calibration of the broadband sector makes the constrained decomposition a testable low-dimensional parametrization. Starting from the second-order Born pure-dephasing equation, we establish the scalar-kernel normalization and derive an exact four-dimensional state-space realization. The associated rational transfer function yields a quartic characteristic equation, explicit Routh–Hurwitz stability conditions, and a pole-residue criterion for observable revival. Complete positivity is certified independently through the necessary and sufficient condition <span>(|G(t)|le 1)</span>. For ideal longitudinal toggling, we define a controlled extension of the effective-kernel model and obtain the Hahn-echo response by piecewise matrix-exponential propagation using the same parameters as the Ramsey dynamics, without a Gaussian cumulant approximation, an infinitely narrow spectral line, or a protocol-dependent amplitude. Dimensionless maps separate completely positive revival, spectrally stable but non-CP dynamics, and spectral instability. A synthetic cross-protocol benchmark further shows that restricted one-component kernels fitted to Ramsey data can reproduce the overall free-induction decay while failing to predict the corresponding echo response. The framework therefore connects structured environmental scales, modal dynamics, physical admissibility, and controlled-coherence prediction within a unified analytically tractable model.</p></div>","PeriodicalId":746,"journal":{"name":"Quantum Information Processing","volume":"25 9","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-similarity microwave-to-optical frequency conversion via three-wave mixing","authors":"Chong Wu,&nbsp;Junfei Chen,&nbsp;Zhiping Wang,&nbsp;Zhixiang Huang","doi":"10.1007/s11128-026-05330-x","DOIUrl":"10.1007/s11128-026-05330-x","url":null,"abstract":"<div><p>We present a demonstration of converting a microwave field to an optical field via three-wave mixing (TWM) in the cold atoms, where the microwave field carries orbital angular momentum (OAM). We show that the conversion allows the structural information of the microwave field to be coherently transferred to the optical field. With the current energy level scheme, we achieve a high-similarity transfer of the intensity and phase information. Our proposed scheme provides a way to realize OAM transmission and spiral phase regulation in cold atoms, and may find some applications in Quantum Information Processing.\u0000</p></div>","PeriodicalId":746,"journal":{"name":"Quantum Information Processing","volume":"25 9","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Bi-directional multi-solution scalable Grover search Algorithm","authors":"Debanjan Konar,&nbsp;Zain Hafeez,&nbsp;Vaneet Aggarwal","doi":"10.1007/s11128-026-05328-5","DOIUrl":"10.1007/s11128-026-05328-5","url":null,"abstract":"<div><p>Grover’s search algorithms, including various partial Grover searches (PGS), experience scaling problems when multiple solutions are sought, as the number of iterations increases with the number of solutions or marked states, making implementation more computationally expensive. Inspired by recent PGS algorithms for multi-solution searchers, this article proposes a scalable Grover quantum search algorithm, referred to as Bi-directional Multi-solution scalable Grover Search (BMGS), to efficiently search for an arbitrary number of solutions from an unstructured database. We introduced a novel multi-segment bidirectional search tactic with PGS across multiple equal segments of each state, starting from an initial state and multiple marked states in parallel, obviating the need for merge operations. We have shown in this work that for each solution our novel approach requires at most <span>(sqrt{mathcal {N}}left( 1- sqrt{frac{1}{b^{lfloor frac{r}{dk}rfloor }}}right) )</span> iterations (here, <span>(mathcal {N}=2^r)</span> elements, <span>(k=log _2 b)</span>, <i>d</i> is the number of equal segments on <i>r</i> qubits, and <i>b</i> is the branching factor). Our proposed BMGS algorithm is benchmarked against state-of-the-art Depth-First Grover Search (DFGS) and PGS implementations for an arbitrary number of solutions, ranging from 2 to 20 qubits, as a proof of concept. We also show that our BMGS requires fewer iterations for shallow quantum circuits and achieves an optimal <span>(mathcal {O})</span>(<span>(sqrt{smathcal {N}})</span>) average complexity for <i>s</i> solutions, when <span>(dk &lt; r)</span>. The Qiskit Python implementation of the proposed BMGS algorithm is available on GitHub (https://github.com/hafeezzwiz21/Multi-Solution-DFGS-BMGS).\u0000</p></div>","PeriodicalId":746,"journal":{"name":"Quantum Information Processing","volume":"25 9","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11128-026-05328-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}