Quantum Cryptography & Cybersecurity: Post-Quantum Security & QKD
Post-quantum cryptography news: NIST PQC standards, quantum-safe security, quantum key distribution. Quantum threats & encryption updates.
Quantum computing poses an existential threat to current encryption infrastructure while simultaneously offering unprecedented security through quantum cryptographic protocols. The cybersecurity community faces a dual imperative: migrating to post-quantum cryptographic standards resistant to quantum attacks while deploying quantum key distribution (QKD) for long-term information security.
Post-Quantum Cryptography (PQC) standards from NIST include CRYSTALS-Kyber (lattice-based key encapsulation), CRYSTALS-Dilithium (lattice-based digital signatures), SPHINCS+ (hash-based signatures), and FALCON. These algorithms rely on mathematically hard problems believed resistant to quantum attacks.
India's Quantum Cryptography and Cybersecurity Initiatives
India's National Quantum Mission includes quantum communication as one of four verticals with substantial allocation. The Thematic Hub on Quantum Communication at IIT Madras, established as the IITM C-DOT Samgnya Technologies Foundation, focuses on quantum cryptography, post-quantum security, quantum key distribution networks, quantum memory, quantum repeaters, and satellite-enabled quantum communication.
The Department of Telecommunications (DoT) and Ministry of Electronics and Information Technology (MeitY) coordinate quantum-safe migration for critical infrastructure. The Defence Research and Development Organisation (DRDO) leads quantum-safe security scheme design and testing according to NQM documentation.
Bengaluru-based QNu Labs, selected under NQM startup support in November 2024, develops quantum-safe cryptography and secure communication systems including QKD systems and quantum random number generators for defense, telecom, and data security applications.
The NQM targets developing quantum-resilient encryption and post-quantum cryptographic frameworks for India's critical infrastructure, with satellite-based secure quantum communications over 2000km and inter-city quantum key distribution as specific deliverables.
quantum-computingOperator-Algebraic Methods for Asymptotic-Preserving Quantum Simulation of Open Systems
--> Quantum Physics arXiv:2605.18886 (quant-ph) [Submitted on 16 May 2026] Title:Operator-Algebraic Methods for Asymptotic-Preserving Quantum Simulation of Open Systems Authors:M.W. AlMasri View a PDF of the paper titled Operator-Algebraic Methods for Asymptotic-Preserving Quantum Simulation of Open Systems, by M.W. AlMasri View PDF HTML (experimental) Abstract:We develop a mathematically rigorous framework for simulating \emph{multiscale physical systems} using quantum computational resources, by translating the \emph{language of asymptotic-preserving (AP) schemes} into the formalism of quantum channels and Lindbladian dynamics. For stiff open quantum systems governed by singularly perturbed generators $\cL_\eps = \eps^{-1}\cL_{\mathrm{fast}} + \cL_{\mathrm{slow}}$ with $\eps \to 0$, we prove that layered quantum protocols, which implement fast-scale relaxation via native analog evolution or analytic manifold projection, converge uniformly in the diamond norm to consistent discretizations of the limiting slow dynamics, with explicit error bound $\mathcal{O}(\eps\Delta t + \Delta t^2)$ independent of stiffness. We establish precise resource-complexity bounds showing that superlinear gate-count savings $\Omega(\kappa\cdot(d_{\mathrm{tot}}/d_{\mathrm{slow}})^c)$ arise if and only if fast dynamics are resolved via (i) hardware-native analog evolution, or (ii) analytic adiabatic elimination reducing effective Hilbert space dimension. The framework is illustrated through cavity QED in the bad-cavity limit and a quantum-inspired AP discretization of kinetic equations converging to fluid limits, with quantified error propagation in trace and diamond norms. This work provides a principled mathematical bridge between classical multiscale numerical analysis and quantum simulation algorithms. Comments: Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2605.18886 [quant-ph] (or arXiv:2605.18886v1 [quant-ph] for this version) https://doi.org/10.48550/arXiv.2605.1
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quantum-computingAssisted quantum teleportation
--> Quantum Physics arXiv:2605.18896 (quant-ph) [Submitted on 17 May 2026] Title:Assisted quantum teleportation Authors:Mithilesh Kumar, Kaavya Iyer View a PDF of the paper titled Assisted quantum teleportation, by Mithilesh Kumar and Kaavya Iyer View PDF Abstract:Teleportation through a non-maximally entangled pair, e.g., $\ket{\psi(\theta)}_{AB}=\cos\theta\ket{00}+\sin\theta\ket{11}$, induces a noisy channel and cannot achieve deterministic unit-fidelity transmission unless $\theta=\pi/4$. We introduce a framework of \emph{assisted quantum teleportation} in which a third party (the ``Bank'') supplies auxiliary multipartite entanglement to restore a perfect Bell pair on the original $AB$ registers. We analyze two operational roles for the Bank: a Bank-measures model (measurement and broadcast) and a transfer model (the Bank transfers its subsystem and then leaves). For GHZ-class and W-class assistance we derive explicit feasibility regions for deterministic restoration and show an operational inequivalence for W resources. We further characterize finite-shot optimal success probabilities for probabilistic restoration and formulate Bank-measures feasibility for general pure Bank resources as a minimax optimization. Comments: Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2605.18896 [quant-ph] (or arXiv:2605.18896v1 [quant-ph] for this version) https://doi.org/10.48550/arXiv.2605.18896 Focus to learn more arXiv-issued DOI via DataCite (pending registration) Submission history From: Mithilesh Kumar [view email] [v1] Sun, 17 May 2026 10:38:52 UTC (117 KB) Full-text links: Access Paper: View a PDF of the paper titled Assisted quantum teleportation, by Mithilesh Kumar and Kaavya IyerView PDFTeX Source view license Current browse context: quant-ph < prev | next > new | recent | 2026-05 References & Citations INSPIRE HEP NASA ADSGoogle Scholar Semantic Scholar export BibTeX citation Loading... BibTeX formatted citation ×
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quantum-computingQuantum eMotion and JMEM TEK Execute Consortium Agreement for Hardware Root-of-Trust SoC Development
Quantum eMotion and JMEM TEK Execute Consortium Agreement for Hardware Root-of-Trust SoC Development Quantum eMotion Corp. (QeM) and Taiwan-based secure semiconductor designer JMEM TEK have executed an international project consortium agreement to develop a quantum-resilient Universal Security System-on-Chip (SoC). The contract solidifies a memorandum of understanding signed in September 2025 and transitions the partnership into a structured R&D phase under the Canada–Taiwan 2024–25 Collaborative R&D Program (CIIP). The joint venture establishes a operational runtime extending through June 30, 2027, governed by a multi-organizational steering committee and specialized technical working groups. Commercial revenues generated by the resulting security hardware platform will be shared proportionally based on a valuation model to be finalized before market entry. Technical Architecture & Specifications / Operational Implementation The technical framework combines QeM’s proprietary electron-tunneling diode-based quantum entropy source with JMEM TEK’s secure chip design infrastructure. The chip architecture integrates a Physical Unclonable Function (PUF), Post-Quantum Cryptography (PQC) accelerators, and hardware root-of-trust subsystems to support encrypted boot processes. Under the project schedule, the engineering pipeline requires the delivery of an initial SoC prototype, peripheral component interconnect express (PCIe) boards, and dedicated server appliances intended for Cryptography-as-a-Service (CaaS) and Entropy-as-a-Service (EaaS) deployments. The engineering team will also produce cryptographic software development kits (SDKs), application programming interfaces (APIs), and compliance data mapped to FIPS 140-3 and Federal Risk and Authorization Management Program (FedRAMP) standards. Strategic Positioning & Ecosystem Integration The joint program targets hardware-level deployment across high-assurance fields, including artificial intelligence data
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quantum-computingPre-Channel Entanglement Shaping Achieves Fundamental Superiority over Post-Distillation: A Geometric Entropy Perspective
--> Quantum Physics arXiv:2605.16463 (quant-ph) [Submitted on 15 May 2026] Title:Pre-Channel Entanglement Shaping Achieves Fundamental Superiority over Post-Distillation: A Geometric Entropy Perspective Authors:Gang Lyu, Wenlong Sun, Yuanfeng Jin, Hua Nan View a PDF of the paper titled Pre-Channel Entanglement Shaping Achieves Fundamental Superiority over Post-Distillation: A Geometric Entropy Perspective, by Gang Lyu and 2 other authors View PDF HTML (experimental) Abstract:Traditional entanglement distillation follows a post-processing paradigm, a noisy quantum state, after full transmission through a noisy channel, is treated as a static resource to be purified via LOCC (local operations and classical communication). This work demonstrates a fundamentally different paradigm,pre-channel entanglement shaping (PES) -- actively engineering the system-environment coupling before or during channel transmission -- achieves a level of purification capability that is physically unattainable by any post-distillation protocol. We prove this separation using the framework of geometric entropy (quantum relative entropy to separable states). In post-distillation, the protocol can only select low-entropy sub-ensembles from a fixed mixed state, leaving the global geometric entropy unchanged or increased. In contrast, PES \textit{suppresses the rate of geometric entropy production} during channel evolution, resulting in a final state whose relative entropy of entanglement strictly exceeds the maximum achievable by post-distillation from the same channel. We provide explicit qubit channel examples, numerical simulations (with complete code in Appendix), and a geometric interpretation on the state manifold. Our result establishes pre-channel entanglement shaping as a distinct operational resource class, with immediate implications for quantum repeaters and entanglement-assisted communication. Very recently, Li \textit{et al.} experimentally demonstrated that preprocessing the entan
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quantum-computingBeyond Bell Teleportation: Machine-Learned Adaptive Protocols
--> Quantum Physics arXiv:2605.16467 (quant-ph) [Submitted on 15 May 2026] Title:Beyond Bell Teleportation: Machine-Learned Adaptive Protocols Authors:Krishnajith C Vinod, N C Randeep View a PDF of the paper titled Beyond Bell Teleportation: Machine-Learned Adaptive Protocols, by Krishnajith C Vinod and 1 other authors View PDF HTML (experimental) Abstract:Quantum teleportation have a central role in quantum information science and allows transferring of an unknown quantum state through entanglement and classical communication. Unfortunately, the interaction with external and internal noise severely affects the quality of teleportation and poses limitations on practical applications of quantum communication networks. In this work, instead of conventional Bell teleportation, we introduce a Machine Learned adaptive protocol for optimizing multiple components of Quantum Teleportation in order to achieve higher fidelity in various noise environments. In order to demonstrate the performance of the proposed scheme, we study three different noise models, including bit-flip, amplitude damping, and depolarizing noise, both in case of single-qubit and two-qubit channels. As a result, we observe substantial improvement in the teleportation fidelity in comparison to the classical Bell-state teleportation protocol in certain noise conditions. Furthermore, the machine-learned protocol reveals a nontrivial strategy for compensation of decoherence and information losses. In addition, obtained results indicate the flexibility and reliability of the proposed framework for implementing various adaptive quantum communications while shedding light on possibilities of discovery of optimal quantum algorithms by means of automated approache Comments: Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2605.16467 [quant-ph] (or arXiv:2605.16467v1 [quant-ph] for this version) https://doi.org/10.48550/arXiv.2605.16467 Focus to learn more arXiv-issued DOI via DataCite (pending re
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quantum-computingSpatially Adaptive Detection for Satellite-based QKD under Atmospheric Turbulence Channel
--> Quantum Physics arXiv:2605.16678 (quant-ph) [Submitted on 15 May 2026] Title:Spatially Adaptive Detection for Satellite-based QKD under Atmospheric Turbulence Channel Authors:Yaoxuan Yang, Ivi Afxenti, Majid Safari View a PDF of the paper titled Spatially Adaptive Detection for Satellite-based QKD under Atmospheric Turbulence Channel, by Yaoxuan Yang and 2 other authors View PDF HTML (experimental) Abstract:Quantum key distribution (QKD) provides information-theoretic security and satellite-based quantum key distribution (SatQKD) has demonstrated the potential to extend this communication security to intercontinental scales. However, atmospheric turbulence induces significant distortion in the spatial distribution of received optical beams, while background noise remains approximately uniform across the detector plane. As a result, single-element qubit (quantum bit) detection can be frequently dominated by noise due to the random spatial pattern of the imaged wavefront, thereby degrading the system performance. To address this limitation, we propose to exploit the spatial degrees of freedom of single-photon detector arrays to reject the excessive noise while adapting to channel variations induced by turbulence. We develop a threshold-based selection method that only activates detector elements that have higher probability of registering qubits. We evaluate the performance of the proposed noise-rejection QKD schemes using Monte Carlo simulations considering the impact of diffraction and atmospheric turbulence on the transmitted optical beam in the presence of background and dark noise. The results show that, compared to conventional schemes, the proposed noise-rejection strategy effectively reduces the quantum bit error rate (QBER) and improves the secret key rate (SKR) performance, while the performance gains depend on the turbulence condition. These findings demonstrate the potential of adaptive array receiver design to enhance the robustness of the SatQKD syst
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quantum-computingCentral Limit Theorem for Bosonic Quantum Channels
--> Quantum Physics arXiv:2605.16782 (quant-ph) [Submitted on 16 May 2026] Title:Central Limit Theorem for Bosonic Quantum Channels Authors:Hami Mehrabi, Ludovico Lami, Mark M. Wilde View a PDF of the paper titled Central Limit Theorem for Bosonic Quantum Channels, by Hami Mehrabi and 2 other authors View PDF HTML (experimental) Abstract:In this paper, we develop an extension of the Central Limit Theorem (CLT) to the setting of bosonic quantum channels. This extension provides a deeper understanding of Gaussian bosonic channels as extremal objects. Using our CLT for bosonic quantum channels, we recover both the classical CLT and the CLT for bosonic quantum states, thereby offering a unified perspective that connects classical probability theory with continuous-variable quantum systems. Moreover, using our result, we can provide necessary uncertainty relations that every physical (possibly non-Gaussian) bosonic quantum channel must satisfy. As another application of our limit theorems, we derive tight lower bounds on the energy-constrained quantum capacity of linear bosonic channels by relating it to the capacity of their associated Gaussian bosonic channels, further reinforcing the role of Gaussian channels as extremal. Comments: Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2605.16782 [quant-ph] (or arXiv:2605.16782v1 [quant-ph] for this version) https://doi.org/10.48550/arXiv.2605.16782 Focus to learn more arXiv-issued DOI via DataCite (pending registration) Submission history From: Hami Mehrabi [view email] [v1] Sat, 16 May 2026 03:29:39 UTC (78 KB) Full-text links: Access Paper: View a PDF of the paper titled Central Limit Theorem for Bosonic Quantum Channels, by Hami Mehrabi and 2 other authorsView PDFHTML (experimental)TeX Source view license Current browse context: quant-ph < prev | next > new | recent | 2026-05 References & Citations INSPIRE HEP NASA ADSGoogle Scholar Semantic Scholar export BibTeX citati
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quantum-computingNIST Advances Nine Post-Quantum Digital Signature Candidates to Third Evaluation Round
NIST Advances Nine Post-Quantum Digital Signature Candidates to Third Evaluation Round The National Institute of Standards and Technology (NIST) has transitioned nine cryptographic algorithms to the third round of its Additional Digital Signature Selection Project, as detailed in NIST Internal Report (IR) 8610. Initiated in September 2022 to diversify the post-quantum cryptography (PQC) portfolio beyond structured lattice-based designs—such as the previously standardized ML-DSA and FN-DSA schemes—the project tracks general-purpose signatures optimized for alternative security assumptions, short signatures, and accelerated verification. The second evaluation round concluded on May 14, 2026, following 18 months of public cryptanalysis, performance benchmarking, and architectural updates presented at the Sixth NIST PQC Standardization Conference in September 2025. Five algorithms—CROSS, LESS, Mirath, PERK, and RYDE—were eliminated from further standardization consideration due to uncompetitive performance trade-offs or security vulnerabilities identified during the second round. Technical Architecture & Specifications / Operational Implementation The nine advancing candidates are categorized across four distinct mathematical modalities: lattice-based, isogeny-based, Multi-Party Computation in the Head (MPCitH), and multivariate cryptography. HAWK, the sole lattice-based advance, utilizes integer-only arithmetic over cyclotomic rings to solve the Search Module Lattice Isomorphism Problem (smLIP) of rank 2 and the One-More-Shortest-Vector Problem (omSVP), avoiding the floating-point dependencies of Falcon. SQIsign relies on the hardness of finding isogenies between supersingular elliptic curves, incorporating higher-dimensional isogenies in its structural redesign to compress public-key and signature sizes to 148 bytes at security category 1. The MPCitH category comprises FAEST, MQOM, and SDitH; FAEST implements the VOLE-in-the-Head framework via the QuickSilver prot
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quantum-computingWD securing disk drives with post-quantum cryptography - Blocks & Files
WD securing disk drives with post-quantum cryptography Blocks & Files
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quantum-computingQuantum Computing News: XNDU Revenue Jumps, Nord Hits $1.4 Billion, and Banks Face a Quantum Security Risk - TipRanks
Quantum Computing News: XNDU Revenue Jumps, Nord Hits $1.4 Billion, and Banks Face a Quantum Security Risk TipRanks
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quantum-computingIs post-quantum crypto in Web3 real preparation or just long-term narrative building?
The QAN XLINK desktop app release feels like another example of Web3 trying to position itself around post-quantum security before it’s actually needed. Most chains still rely on cryptography that could be vulnerable if large-scale quantum computing ever becomes practical, especially around wallet signatures and asset security. XLINK’s approach leans more toward compatibility than replacement, adding a quantum-safe layer on top of existing Ethereum tools like MetaMask instead of forcing users to migrate. I think that’s the only approach that could realistically work in crypto, because full migration rarely happens unless it’s absolutely unavoidable. That said, I’m not convinced yet whether this is meaningful early infrastructure or just narrative-building around a threat that may still be far off. Where do you fall on this, legit preparation or premature optimization? submitted by /u/Ge_Yo [link] [comments]
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quantum-computingQuantum Meets Statistical-Physical Secrecy: A Novel Hybrid Key Distribution Architecture
--> Quantum Physics arXiv:2605.15247 (quant-ph) [Submitted on 14 May 2026] Title:Quantum Meets Statistical-Physical Secrecy: A Novel Hybrid Key Distribution Architecture Authors:Ertugrul Basar View a PDF of the paper titled Quantum Meets Statistical-Physical Secrecy: A Novel Hybrid Key Distribution Architecture, by Ertugrul Basar View PDF HTML (experimental) Abstract:This letter proposes a novel hybrid key distribution architecture that jointly exploits quantum key distribution (QKD) and Kirchhoff-law-Johnson-noise (KLJN) statistical-physical key exchange. In the proposed system, an optical BB84-type QKD link operates in coordination with a parallel wired KLJN link, which is used for secure basis handling and, in selected protocols, additional raw key generation. Three novel KLJN-assisted QKD protocols are introduced to eliminate public basis disclosure messages and bit sifting, extract basis-derived key bits, or generate raw key bits under ideal KLJN assumptions. Analytical expressions for the normalized key rate and absolute throughput are derived by accounting for optical channel penalties, KLJN bandwidth constraints, and synchronization bottlenecks. Numerical results show that the proposed hybrid architecture can improve key generation efficiency and throughput in short-haul infrastructures, including metropolitan area networks (MANs) and data center interconnects. Comments: Subjects: Quantum Physics (quant-ph); Cryptography and Security (cs.CR); Information Theory (cs.IT) Cite as: arXiv:2605.15247 [quant-ph] (or arXiv:2605.15247v1 [quant-ph] for this version) https://doi.org/10.48550/arXiv.2605.15247 Focus to learn more arXiv-issued DOI via DataCite (pending registration) Submission history From: Ertugrul Basar [view email] [v1] Thu, 14 May 2026 11:09:06 UTC (136 KB) Full-text links: Access Paper: View a PDF of the paper titled Quantum Meets Statistical-Physical Secrecy: A Novel Hybrid Key Distribution Architecture, by Ertugrul BasarView PDFHTML (
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quantum-computingNIST Advances Nine Candidates to the Third Round of Additional Post-Quantum Digital Signatures
The U.S. National Institute of Standards and Technology (NIST) has advanced nine digital signature algorithms to the third round of its Additional Post-Quantum Cryptography standardization process. These candidates offer diverse options including compact isogeny-based SQIsign and efficient lattice-based HAWK schemes. The selection enhances resilience against quantum threats for applications from IoT devices to software signing and TLS certificates. The post NIST Advances Nine Candidates to the Third Round of Additional Post-Quantum Digital Signatures appeared first on The Qubit Report.
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quantum-computingQuantum Computing Weekly Round-Up: Week Ending May 16, 2026
This quantum computing weekly roundup for the week ending May 16, 2026 showcases impressive hardware progress including silicon spin qubits that teleport states across a chip and the first hybrid rack-mounted quantum computer. Funding continued strongly with Photonic Inc raising over $200 million while post-quantum security efforts gained urgency across governments and industry. Europe demonstrated clear momentum with new academies, supercomputer access, and commercial pilots. The field is rapidly moving from lab curiosity to practical deployment. The post Quantum Computing Weekly Round-Up: Week Ending May 16, 2026 appeared first on The Qubit Report.
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quantum-computingQNu Labs Named Quantum Key Distribution Industry Leader
Insider Brief QNu Labs was recognized as a “Global Established Leader” in the 2026 MarketsandMarkets 360Quadrants Quantum Key Distribution evaluation report. The report assessed more than 170 companies across the global quantum-safe cybersecurity ecosystem, with 17 identified as established leaders. QNu Labs develops quantum-safe communication and encryption technologies for sectors including government, telecom, finance, and critical infrastructure. PRESS RELEASE — QNu Labs (www.qnulabs.com), a global leader in end-to-end hybrid quantum cybersecurity solutions, has been recognised as a ‘Global Established Leader’ in the MarketsandMarkets 360Quadrants Quantum Key Distribution Company Evaluation Report, 2026, a study that assessed over 170 companies across the global quantum-safe security ecosystem, categorizing the top 17 into Established Leaders. The evaluation positions QNu Labs among companies operating in the Quantum Key Distribution market, which is gaining momentum as enterprises and governments prioritize next-generation cybersecurity solutions against emerging quantum computing threats. The report highlights quantum-safe security transitioning from an emerging technology area to a strategic priority, with organisations accelerating adoption of solutions capable of securing long-term data protection. The assessment evaluated over 170 companies across product offering, deployment architecture, transmission medium, revenue, geographic presence, and verticals including BFSI, Government and Defence, Healthcare, and Automotive, with the top 17 recognised as quadrant leaders. Within this evolving landscape, QNu Labs is developing quantum-safe communication and encryption technologies based on Quantum Key Distribution and quantum cryptography frameworks for high-security sectors such as government, defence, BFSI, telecom, and critical infrastructure. As highlighted in the 360Quadrants analysis, the industry is increasingly prioritizing scalable and deployment-ready
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quantum-computingThe Financial Impact of Delaying PQC Migration
Insider Brief Post-quantum cryptography migration is increasingly treated as necessary as quantum computing research progresses. One key variable is cost, which rises as timelines compress and resource demand grows. Organizations beginning earlier work with evolving tools and limited implementation experience. Those that delay encounter tighter timelines, higher demand for specialized resources, and greater coordination challenges. […]
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quantum-computingImaginarity Resource Theory of Gaussian Quantum Channels
--> Quantum Physics arXiv:2605.14299 (quant-ph) [Submitted on 14 May 2026] Title:Imaginarity Resource Theory of Gaussian Quantum Channels Authors:Ting Zhang, Jinchuan Hou, Xiaofei Qi View a PDF of the paper titled Imaginarity Resource Theory of Gaussian Quantum Channels, by Ting Zhang and 2 other authors View PDF HTML (experimental) Abstract:Complex numbers play an indispensable role in quantum mechanics and quantum information, as validated by both theoretical analysis and experimental verification. Since quantum information processing inherently relies on quantum channels, the resource theory for quantum channels is equally fundamental to that for quantum states. In this paper, we propose two frameworks for quantifying the imaginarity of Gaussian channels. The first framework regards all real superchannels as free superchannels. Within this setting, we introduce two concrete imaginarity measures for Gaussian channels: I_s^GC based on existing imaginarity measures of Gaussian states, and I_d^GC derived directly from the intrinsic parameters of Gaussian channels, which enjoys high computational simplicity. The second framework adopts only a proper subset of real superchannels as free superchannels. Under this framework, we put forward another imaginarity measure I_c^GC , which is fully determined by the inherent parameters of Gaussian channels and features continuity as well as tractable computation. As a practical application, we employ I_c^GC to investigate the dynamical behavior of Quantum Brownian Motion Gaussian channels throughout the entire evolutionary process. Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2605.14299 [quant-ph] (or arXiv:2605.14299v1 [quant-ph] for this version) https://doi.org/10.48550/arXiv.2605.14299 Focus to learn more arXiv-issued DOI via DataCite (pending registration) Submission history From: Ting Zhang [view email] [v1] Thu, 14 May 2026 03:05:12 UTC (222 KB) Full-text links: Access Paper: View a PDF of the paper t
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quantum-computingControllable Quantum Memory Capacity in Quantum Reservoir Networks with Tunable partial-SWAPs
--> Quantum Physics arXiv:2605.12713 (quant-ph) [Submitted on 12 May 2026] Title:Controllable Quantum Memory Capacity in Quantum Reservoir Networks with Tunable partial-SWAPs Authors:Erik L. Connerty, Ethan N. Evans View a PDF of the paper titled Controllable Quantum Memory Capacity in Quantum Reservoir Networks with Tunable partial-SWAPs, by Erik L. Connerty and 1 other authors View PDF HTML (experimental) Abstract:In the field of quantum reservoir computing (QRC), many different computational models and architectures have been proposed. From these models, we identify feedback based models -- which use a feedback mechanism to re-embed classical measurements from the QRC -- and recurrent models -- which use a multi-register approach with memory and readout qubits -- as the two major competing architectures that have been discussed and validated on hardware. In this paper, we advance upon the recurrent architectures, which employ a two register approach to endow the QRC with a fading memory. While these approaches have been validated on hardware and have demonstrated great real-world performance on noisy-intermediate-scale-quantum (NISQ) quantum processing units (QPUs), the exact mechanism through which the memory capacity arises is not completely understood or fully controllable. With this, we augment the recurrent approaches and present a hardware-realizable mechanism, which we call a tunable partial-SWAP, that allows for the direct control of the rate of memory dissipation from a QRN implemented on a gate-based QPU. The theory behind this mechanism is discussed in terms of a controlled amplitude-damping channel and validation experiments using a randomized short-term memory capacity (STMC) recall benchmark and the NARMA-5 dataset are conducted using simulation and IBM QPUs, respectively. Comments: Subjects: Quantum Physics (quant-ph); Artificial Intelligence (cs.AI) Cite as: arXiv:2605.12713 [quant-ph] (or arXiv:2605.12713v1 [quant-ph] for this version) &nb
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quantum-computingNumerical security analysis for practical quantum key distribution
--> Quantum Physics arXiv:2605.12984 (quant-ph) [Submitted on 13 May 2026] Title:Numerical security analysis for practical quantum key distribution Authors:Álvaro Navarrete, Guillermo Currás-Lorenzo, Margarida Pereira, Marcos Curty View a PDF of the paper titled Numerical security analysis for practical quantum key distribution, by \'Alvaro Navarrete and 2 other authors View PDF HTML (experimental) Abstract:Quantum key distribution (QKD) promises information-theoretic security based on quantum mechanics and idealized device models. Practical implementations, however, deviate from these models due to unavoidable device imperfections, and existing security proofs fall short of capturing the complexity of real-world systems. Here we introduce a versatile numerical finite-key security framework valid against general coherent attacks and applicable to a broad class of practical QKD setups. It accommodates most relevant imperfections at both transmitter and receiver, including non-independent-and-identically-distributed (non-IID) signals arising in high-speed QKD systems due to the limited bandwidth of optical modulators, while requiring only partial characterization of the apparatuses. We demonstrate the power of our framework by proving the security of a realistic decoy-state QKD implementation with laser sources, providing a practical route towards rigorous security certification of real-world QKD setups. Comments: Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2605.12984 [quant-ph] (or arXiv:2605.12984v1 [quant-ph] for this version) https://doi.org/10.48550/arXiv.2605.12984 Focus to learn more arXiv-issued DOI via DataCite (pending registration) Submission history From: Álvaro Navarrete [view email] [v1] Wed, 13 May 2026 04:27:03 UTC (339 KB) Full-text links: Access Paper: View a PDF of the paper titled Numerical security analysis for practical quantum key distribution, by \'Alvaro Navarrete and 2 other authorsView PDFHTML (experimental)TeX Source v
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quantum-computingResearchers Claim Advance in 3D Self-Correcting Quantum Memory Could Reduce Quantum Computing Error-Correction Overhead - The Quantum Insider
Researchers Claim Advance in 3D Self-Correcting Quantum Memory Could Reduce Quantum Computing Error-Correction Overhead The Quantum Insider
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