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Nonmonotonic Stress Overshoot in Entangled Polymer Melts under Two-step Shear
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作者 Yong-Jin Ruan Ya-Qing Chang +1 位作者 Jiang-Yang Mo Bai-Cheng Mei 《Chinese Journal of Polymer Science》 2026年第1期268-277,I0018,共11页
Shear stress overshoot in entangled polymer rheology is a hallmark of transient dynamics,but its microscopic origin remains under debate.Using molecular dynamics simulations,we investigate a two-step shear protocol co... Shear stress overshoot in entangled polymer rheology is a hallmark of transient dynamics,but its microscopic origin remains under debate.Using molecular dynamics simulations,we investigate a two-step shear protocol consisting of successive startup shears separated by a waiting period,with the first shear interrupted before the overshoot.In the homogeneous flow,the GLaMM theory captures the stress response during the first shear,but fails to reproduce the nonmonotonic dependence of the second stress overshoot(σ_(2max))on the waiting time.Contrary to the prediction of a nonmonotonic normal stress component σ_(yy)during the waiting period,our simulations show that σ_(yy),like the tube segment orientation(S_(xy)),the contour length of the primitive chain(L),and the entanglement number per chain(Z),relaxes monotonically toward equilibrium.At the strain corresponding to σ_(2max),both the tube segment orientation and the entanglement number per chain exhibit a nonmonotonic dependence on the waiting time that closely mirrors the behavior of σ_(2max),indicating that both factors play significant roles in governing(σ_(2max).Our findings are consistent with the interpretation of lanniruberto and Ma rrucci[ACS Macro.Lett.2014,3,552]for orientation effects and with the viewpoint of Wang et al.[Macromolecules 2013,46,3147]for entanglement effects,although the two explanations are rooted in distinct physical pictu res.These results provide new insights into the stress responses of entanglement polymer fluids and underscore the need for a more unified theoretical framework. 展开更多
关键词 entangled polymer rheology Molecular dynamics simulation Tube model DISentangleMENT
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Separability criteria and entanglement witnesses from mutually unbiased equiangular tight frames
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作者 Alexey E Rastegin 《Communications in Theoretical Physics》 2026年第2期35-43,共9页
Methods of quantum information processing often appear in terms of specially selected states.For example,mutually unbiased bases(MUBs)and symmetric informationally complete measurements are widely applied.Finite frame... Methods of quantum information processing often appear in terms of specially selected states.For example,mutually unbiased bases(MUBs)and symmetric informationally complete measurements are widely applied.Finite frames have found use in many areas including quantum information.Due to its specific inner structure,a single equiangular tight frame(ETF)allows one to formulate criteria to detect non-classical correlations.This study aims to approach entanglement detection with the use of mutually unbiased ETFs.Such frames are an interesting generalization of widely recognized MUBs.It still uses rank-one operators,but the number of outcomes can exceed the dimensionality.Several approaches are considered including separability criteria and entanglement witnesses.Separability criteria for multipartite systems are finally obtained. 展开更多
关键词 equiangular tight frames mutual unbiasedness separable states entanglement witnesses
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Volume-law entanglement fragmentation of quasiparticles
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作者 Jiaju Zhang 《Communications in Theoretical Physics》 2026年第1期9-17,共9页
We investigate the entanglement entropy in quantum states featuring repeated sequential excitations of unit patterns in momentum space.In the scaling limit,each unit pattern contributes independently and universally t... We investigate the entanglement entropy in quantum states featuring repeated sequential excitations of unit patterns in momentum space.In the scaling limit,each unit pattern contributes independently and universally to the entanglement entropy,leading to a characteristic volume-law scaling.Crucially,this universal contribution remains identical for both free and interacting models,enabling decomposition of the total entanglement into patternspecific components.Numerical verification in fermionic and bosonic chains confirms this volume-law fragmentation phenomenon.For fermionic systems,we derive analytical expressions where many-body entanglement becomes expressible through few-body entanglement components.Notably,this analytical framework extends to spin-1/2 XXZ chains through appropriate identifications. 展开更多
关键词 entanglement entropy QUASIPARTICLE XXZ chain
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Q-ALIGNer:A Quantum Entanglement-Driven Multimodal Framework for Robust Fake News Detection
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作者 Sara Tehsin Inzamam Mashood Nasir +4 位作者 Wiem Abdelbaki Fadwa Alrowais Reham Abualhamayel Abdulsamad Ebrahim Yahya Radwa Marzouk 《Computers, Materials & Continua》 2026年第5期1670-1700,共31页
The rapid proliferation of multimodal misinformation on social media demands detection frameworks that are not only accurate but also robust to noise,adversarial manipulation,and semantic inconsistency between modalit... The rapid proliferation of multimodal misinformation on social media demands detection frameworks that are not only accurate but also robust to noise,adversarial manipulation,and semantic inconsistency between modalities.Existing multimodal fake news detection approaches often rely on deterministic fusion strategies,which limits their ability to model uncertainty and complex cross-modal dependencies.To address these challenges,we propose Q-ALIGNer,a quantum-inspired multimodal framework that integrates classical feature extraction with quantumstate encoding,learnable cross-modal entanglement,and robustness-aware training objectives.The proposed framework adopts quantumformalism as a representational abstraction,enabling probabilisticmodeling ofmultimodal alignment while remaining fully executable on classical hardware.Q-ALIGNer is evaluated on four widely used benchmark datasets—FakeNewsNet,Fakeddit,Weibo,and MediaEval VMU—covering diverse platforms,languages,and content characteristics.Experimental results demonstrate consistent performance improvements over strong text-only,vision-only,multimodal,and quantum-inspired baselines,including BERT,RoBERTa,XLNet,ResNet,EfficientNet,ViT,Multimodal-BERT,ViLBERT,and QEMF.Q-ALIGNer achieves accuracies of 91.2%,92.9%,91.7%,and 92.1%on FakeNewsNet,Fakeddit,Weibo,and MediaEval VMU,respectively,with F1-score gains of 3–4 percentage points over QEMF.Robustness evaluation shows a reduced adversarial accuracy gap of 2.6%,compared to 7%–9%for baseline models,while calibration analysis indicates improved reliability with an expected calibration error of 0.031.In addition,computational analysis shows that Q-ALIGNer reduces training time to 19.6 h compared to 48.2 h for QEMF at a comparable parameter scale.These results indicate that quantum-inspired alignment and entanglement can enhance robustness,uncertainty awareness,and efficiency in multimodal fake news detection,positioning Q-ALIGNer as a principled and practical content-centric framework for misinformation analysis. 展开更多
关键词 Machine learning fake news detection multimodal learning quantum natural language processing cross-modal entanglement adversarial robustness uncertainty calibration
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Coherence and entanglement dynamics in Shor's algorithm
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作者 Linlin Ye Zhaoqi Wu Shao-Ming Fei 《Communications in Theoretical Physics》 2026年第1期61-70,共10页
Shor's algorithm outperforms its classical counterpart in efficient prime factorization.We explore the coherence and entanglement dynamics of the evolved states within Shor's algorithm,showing that the coheren... Shor's algorithm outperforms its classical counterpart in efficient prime factorization.We explore the coherence and entanglement dynamics of the evolved states within Shor's algorithm,showing that the coherence in each step relies on the dimension of register or the order,and discuss the relations between geometric coherence and geometric entanglement.We investigate how unitary operators induce variations in coherence and entanglement,and analyze the variations of coherence and entanglement within the entire algorithm,demonstrating that the overall effect of Shor's algorithm tends to deplete coherence and produce entanglement.Our research not only deepens the understanding of this algorithm but also provides methodological references for studying resource dynamics in other quantum algorithms. 展开更多
关键词 Shor's algorithm Tsallis relativeαentropy of coherence l_(1 p)norm of coherence geometric coherence geometric entanglement
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Universal Behavior in Entanglement Entropy Reveals Quantum Criticality and Underlying Symmetry Breaking
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作者 Zhe Wang Zehui Deng +5 位作者 Zenan Liu Zhiyan Wang Yi-Ming Ding Long Zhang Wenan Guo Zheng Yan 《Chinese Physics Letters》 2025年第11期341-353,共13页
Entanglement plays a key role in quantum physics, but how much information it can extract from many-body systems is still an open question, particularly regarding quantum criticalities and emergent symmetries. In this... Entanglement plays a key role in quantum physics, but how much information it can extract from many-body systems is still an open question, particularly regarding quantum criticalities and emergent symmetries. In this work, we systematically study the entanglement entropy(EE) and derivative entanglement entropy(DEE) near quantum phase transitions in various quantum many-body systems. A one-parameter scaling relation between the DEE and system size at the critical point has been derived for the first time, which successfully obtains the critical exponent via data collapse. Furthermore, we find that the EE peaks at the(emergent) symmetryenhanced first-order transition, reflecting higher symmetry breaking. This work provides a new paradigm for quantum many-body research from the perspective of EE and DEE. 展开更多
关键词 quantum criticalities derivative entanglement entropy dee entanglement entropy derivative entanglement entropy entanglement entropy ee symmetry breaking emergent symmetries quantum physics
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Enhanced Electron–Electron Entanglement in Few-Cycle Laser-Atom Interactions
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作者 Jingyu Zhang Zhifeng Cao +2 位作者 Xiaolei Hao Weidong Li Jing Chen 《Chinese Physics Letters》 2025年第11期60-74,共15页
The rapid advancements of ultrafast intense laser technology have opened new avenues for investigating entanglement in laser-induced systems. However, the application of these advances in quantum technology requires a... The rapid advancements of ultrafast intense laser technology have opened new avenues for investigating entanglement in laser-induced systems. However, the application of these advances in quantum technology requires a reliable and universally applicable method for enhancing and regulating entanglement. Here we demonstrate how a few-cycle intense laser field can significantly enhance the degree of entanglement compared to its multi-cycle counterpart, using the example of electron–electron entanglement of orbital angular momentum(OAM) states in recollision-excitation non-sequential double ionization of Ar atoms. By confining the ionization dynamics to a specific narrow time window, the few-cycle pulse purifies the electron trajectories, thereby ensuring high coherence between entangled OAM channels and enhancing entanglement. Furthermore, the degree of entanglement can be efficiently modulated by varying the carrier envelope phase of the few-cycle laser pulse, which is achieved by altering the population across OAM channels. Optimizing coherence through electron trajectory purification with a designed specific temporal waveform of laser field provides a general pathway for enhancing entanglement in laser-induced systems. 展开更多
关键词 ultrafast intense laser technology orbital angular momentum electron electron entanglement orbit enhance degree entanglement few cycle laser enhancing regulating entanglement quantum technology electron electron entanglement
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Generating Entangled Pairs of Vortex Photons via Induced Emission
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作者 D.V.Grosman G.K.Sizykh +2 位作者 E.O.Lazarev G.V.Voloshin D.V.Karlovets 《Chinese Physics Letters》 2025年第12期115-125,共11页
Pairs of entangled vortex photons can promise new prospects of application in quantum computing and cryptography.We investigate the possibility of generating such states via two-level atom emission induced by a single... Pairs of entangled vortex photons can promise new prospects of application in quantum computing and cryptography.We investigate the possibility of generating such states via two-level atom emission induced by a single photon wave packet with a definite total angular momentum(TAM).The entangled pair produced in this process possesses well-defined mean TAM with the TAM variation being much smaller than h.On top of that,the variation exponentially decreases with the increase in TAM of the incident photon.Our model allows one to track the time evolution of the state of the entangled pair.An experimentally feasible scenario is assumed,in which the incident photon interacts with a spatially confined atomic target.We conclude that induced emission can be used as a source of entangled vortex photons with applications in atomic physics experiments,quantum optics,and quantum information sciences. 展开更多
关键词 entangled vortex photons total angular momentum tam incident photonour entangled pair quantum computing photon wave vortex photons entangled photons
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Cloning scheme for multipartite entangled pure states via photonic quantum walk
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作者 WANG Guocui LIN Zhi +2 位作者 LI Xikun YANG Qing YANG Ming 《量子电子学报》 北大核心 2025年第2期206-216,共11页
The no-cloning theorem has sparked considerable interest in achieving high-fidelity approximate quantum cloning.Most of the previous studies mainly focused on the cloning of single particle states,and cloning schemes ... The no-cloning theorem has sparked considerable interest in achieving high-fidelity approximate quantum cloning.Most of the previous studies mainly focused on the cloning of single particle states,and cloning schemes used there are incapable of cloning quantum entangled states in multipartite systems.Few schemes were proposed for cloning multiparticle states,which consume more entanglement resources with loss of qubits,and the fidelity of the cloned state is relatively low.In this paper,cloning schemes for bipartite and tripartite entangled states based on photonic quantum walk and entanglement swapping are proposed.The results show that according to the proposed schemes,two high-fidelity(up to 0.75)cloned states can be obtained with less quantum resource consumption.Because of the simple cloning steps,few quantum resources and high fidelity,these schemes are both efficient and feasible.Moreover,this cloning machine eliminates the need for tracing out cloning machine,thereby minimizing resource waste. 展开更多
关键词 quantum optics entanglement cloning photonic quantum walk multipartite entanglement
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Established conversions for hybrid entangled states assisted by error-predicted parity-discriminated devices
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作者 Fang-Fang Du Zhi-Guo Fan +2 位作者 Xue-Mei Ren Ming Ma Wen-Yao Liu 《Chinese Physics B》 2025年第1期72-78,共7页
Hybrid entangled states are crucial in quantum physics,offering significant benefits for hybrid quantum communication and quantum computation,and then the conversion of hybrid entangled states is equally critical.This... Hybrid entangled states are crucial in quantum physics,offering significant benefits for hybrid quantum communication and quantum computation,and then the conversion of hybrid entangled states is equally critical.This paper presents two novel schemes,that is,one converts the two-qubit hybrid Knill–Laflamme–Milburn(KLM)entangled state into Bell states and the other one transforms the three-qubit hybrid KLM state into Greenberger–Horne–Zeilinger(GHZ)states assisted by error-predicted and parity-discriminated devices.Importantly,the integration of single photon detectors into the parity-discriminated device enhances predictive capabilities,mitigates potential failures,and facilitates seamless interaction between the nitrogen-vacancy center and photons,so the two protocols operate in an error-predicted way,improving the experimental feasibility.Additionally,our schemes demonstrate robust fidelities(close to 1)and efficiencies,indicating their feasibility with existing technology. 展开更多
关键词 quantum information processing quantum entanglement quantum communication entanglement conversion
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Measurement-based entanglement purification for hybrid entangled state
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作者 Cheng-Chen Luo Shi-Pu Gu +2 位作者 Xing-Fu Wang Lan Zhou Yu-Bo Sheng 《Chinese Physics B》 2025年第3期104-114,共11页
Hybrid entangled states(HESs),which involve different particles with various degrees of freedom,have garnered significant attention and been applied in a wide range of quantum technologies.However,similar to other cat... Hybrid entangled states(HESs),which involve different particles with various degrees of freedom,have garnered significant attention and been applied in a wide range of quantum technologies.However,similar to other categories of entanglement,maximally HESs inevitably degrade to mixed states due to the environmental noise and operational imperfections.To address the degradation problem,measurement-based entanglement purification offers a feasible and robust solution alternative to conventional gate-based purification methods.In this paper,we propose a measurement-based hybrid entanglement purification protocol(MB-HEPP)for a certain kind of HES which consists of polarization photons and coherent states.We extend our methodology to several conditions,such as the multi-copy and multi-party scenarios,and the photon-loss condition.Compared with previous HEPPs,this protocol has several advantages.First,it does not depend on post-selection and the purified HESs can be retained for further application.Second,it does not require the Bell state measurement,but only uses the parity check with conventional linear optical elements,which makes it have the higher success probability and more feasible.Our MB-HEPP has potential applications in future heterogeneous quantum networks. 展开更多
关键词 hybrid entanglement measurement-based entanglement purification parity check
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Quantum-enhanced time-of-arrival measuring method based on partially entangled state
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作者 Peng-Xian Li Lu-Ping Xu +1 位作者 Gui-Ting Hu Wen-Long Gao 《Chinese Physics B》 2025年第7期197-210,共14页
We present a quantum ranging protocol that overcomes photon-loss limitations using optimized partially frequencyentangled states.By establishing the fundamental relationship between the degree of entanglement,channel ... We present a quantum ranging protocol that overcomes photon-loss limitations using optimized partially frequencyentangled states.By establishing the fundamental relationship between the degree of entanglement,channel transmission efficiency and measurement precision,we demonstrate superclassical timing resolution in both lossless and lossy regimes.Theoretical analysis and numerical simulations reveal that,under a lossless channel,the precision gain increases with the degree of entanglement,approaching the Heisenberg limit.Importantly,in lossy channels,the precision gain is significantly influenced by both the channel transmission efficiency and the degree of entanglement.For transmission efficiencies above50%,the proposed method provides up to 1.5 times the precision gain of classical methods when entanglement parameters are optimized.Moreover,by optimizing intra-group and inter-group covariances in the multi-structured entangled state,we achieve substantial precision gains even at low transmission efficiencies(~30%),demonstrating its robustness against loss.This study resolves the critical trade-off between entanglement-enhanced precision and loss-induced information degradation.Future implementation could extend to satellite-based quantum positioning,remote sensing,quantum illumination,and other fields that require high-precision ranging in lossy environments.The protocol establishes a universal framework for loss-tolerant quantum metrology,advancing the practical deployment of quantum-enhanced sensing in real-world applications. 展开更多
关键词 quantum ranging partially entangled state degree of entanglement
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Entanglement Signatures of(2+1)D Dirac Fermions Subjected to Randomness
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作者 Qijie Zhang Weiwei Chen +2 位作者 Wei Li Qunxiang Li W.Zhu 《Chinese Physics Letters》 2025年第10期290-304,共15页
In this work,we investigate disordered Dirac fermions from the perspective of quantum entanglement,which provides a different angle compared to the ordinary perturbative renormalization group(RG)analysis.We consider D... In this work,we investigate disordered Dirac fermions from the perspective of quantum entanglement,which provides a different angle compared to the ordinary perturbative renormalization group(RG)analysis.We consider Dirac fermions subjected to random hopping and random flux,which respectively fall into the chiral Gaussian orthogonal ensemble(cGOE)and chiral Gaussian unitary ensemble(cGUE)universality classes.Existing studies based on perturbative calculations suggest that both types of randomness are marginal.Here,through numerical simulations of the corresponding lattice models,we find that these two different types of randomness exhibit distinct entanglement features,signaling completely different properties in contrast to the perturbative RG analysis.In particular,although the entropy area-law is generally held for both types of randomness,we identify that the subleading term of the entanglement entropy is enhanced by random flux but not by random hopping.This subleading term is known as the entropic F-function in the clean limit without disorder.Our observations indicate that disordered theories in cGOE and cGUE are essentially different,which recalls careful analysis on the RG calculations. 展开更多
关键词 disordered dirac fermions quantum entanglementwhich entangleMENT perturbative calculations dirac fermions chiral gaussian orthogonal ensemble cgoe random hopping chiral gaussian unitary
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Machine Learning Enabled Reusable Adhesion,Entangled Network‑Based Hydrogel for Long‑Term,High‑Fidelity EEG Recording and Attention Assessment 被引量:1
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作者 Kai Zheng Chengcheng Zheng +9 位作者 Lixian Zhu Bihai Yang Xiaokun Jin Su Wang Zikai Song Jingyu Liu Yan Xiong Fuze Tian Ran Cai Bin Hu 《Nano-Micro Letters》 2025年第11期514-529,共16页
Due to their high mechanical compliance and excellent biocompatibility,conductive hydrogels exhibit significant potential for applications in flexible electronics.However,as the demand for high sensitivity,superior me... Due to their high mechanical compliance and excellent biocompatibility,conductive hydrogels exhibit significant potential for applications in flexible electronics.However,as the demand for high sensitivity,superior mechanical properties,and strong adhesion performance continues to grow,many conventional fabrication methods remain complex and costly.Herein,we propose a simple and efficient strategy to construct an entangled network hydrogel through a liquid-metal-induced cross-linking reaction,hydrogel demonstrates outstanding properties,including exceptional stretchability(1643%),high tensile strength(366.54 kPa),toughness(350.2 kJ m^(−3)),and relatively low mechanical hysteresis.The hydrogel exhibits long-term stable reusable adhesion(104 kPa),enabling conformal and stable adhesion to human skin.This capability allows it to effectively capture high-quality epidermal electrophysiological signals with high signal-to-noise ratio(25.2 dB)and low impedance(310 ohms).Furthermore,by integrating advanced machine learning algorithms,achieving an attention classification accuracy of 91.38%,which will significantly impact fields like education,healthcare,and artificial intelligence. 展开更多
关键词 entangled network Reusable adhesion Epidermal sensor Machine learning Attention assessment
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Dielectric-mechanical couple effect of COF cyanate derived from dual functions of molecular interaction and chain entanglement 被引量:1
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作者 Feifan Cai Ruoyu Chen +4 位作者 Qichao Dong Wansong Gu Kai Zheng Longjiang Deng Hetao Chu 《Journal of Materials Science & Technology》 2025年第27期10-20,共11页
The rapid advancement of radar and 5 G communication technologies has created an urgent need for materials that possess both low dielectric constants and superior mechanical strength to ensure efficient signal transmi... The rapid advancement of radar and 5 G communication technologies has created an urgent need for materials that possess both low dielectric constants and superior mechanical strength to ensure efficient signal transmission and minimal loss.Herein,a synergistic effect of multiple regulation strategies from the atomic scales to the molecular scales was proposed to develop Covalent Organic Frameworks(COFs)modified cyanate ester resins(COF-mCE).The strategy has proven highly effective in enhancing both dielectric and mechanical properties.With only 3 wt%COFs,the dielectric constant of COF-mCE is reduced from 3.32 to 2.84 at 1 MHz.Meanwhile,the mechanical performance of COF-mCE composites exhibits substantial improvements,with flexural strength increasing by 42.6% and tensile strength by 52.1% compared to pure mCE.The investigation explores that hydrogen bonding and π-π stacking interactions restrain the polarization feature and the mechanical property improvements of the COF-mCE derived from the entanglement effect of COF-polymer chains.Furthermore,the 3D-printed COF-mCE honeycomb structure demonstrates excellent electromagnetic wave transmittance and low reflectance,achieving a transmittance of 94.1% at 10 GHz with a 60°incidence angle.This multi-scale design strategy offers new insights into the development of low-k dielectric material for next-generation electronic science applications. 展开更多
关键词 Low-k materials Chain entanglement Molecular interaction 3D print
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Harnessing the mechanical properties of Gelatin methacryloyl hydrogels through cooling-induced entanglement
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作者 Kerong Wu Wei Jian +2 位作者 Zhongwei Meng Kailei Xu Ji Lin 《Theoretical & Applied Mechanics Letters》 2025年第6期610-617,共8页
Enhancing gelatin methacryloyl(GelMA)hydrogel mechanics without compromising biocompatibility remains challenging,as conventional chemical crosslinking often disrupts degradation behavior.A cooling-induced entan-gleme... Enhancing gelatin methacryloyl(GelMA)hydrogel mechanics without compromising biocompatibility remains challenging,as conventional chemical crosslinking often disrupts degradation behavior.A cooling-induced entan-glement strategy effectively improves mechanical performance while preserving biological properties;however,its underlying mechanisms remain unclear.This study demonstrates that extended cooling durations significantly enhance the mechanical properties of GelMA hydrogels.Microstructural analyses reveal cooling-induced forma-tion of compact polymer networks with reduced mesh sizes.Molecular dynamics(MD)simulations confirm that the cooling process promotes topological entanglements that govern mechanical reinforcement.Guided by these insights,we propose a theoretical model to predict the stress responses of GelMA hydrogels under various cooling durations,establishing quantitative correlations between entanglement mechanisms and mechanical outcomes.This study provides a fundamental understanding of the interplay between cooling conditions,microstructure,and mechanical performance,offering a robust framework for designing GelMA hydrogels with optimized me-chanical properties for advanced biomedical applications. 展开更多
关键词 HYDROGEL entangleMENT VISCOELASTICITY Constitutive model
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Classification of entanglement distribution using machine learning
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作者 F El Ayachi H Ait Mansour M El Baz 《Communications in Theoretical Physics》 2025年第6期76-86,共11页
A classification of multipartite entanglement is introduced for pure and mixed states.The classification is based on the distribution of entanglement between the qubits of a given system,with a mathematical framework ... A classification of multipartite entanglement is introduced for pure and mixed states.The classification is based on the distribution of entanglement between the qubits of a given system,with a mathematical framework used to characterize fully entangled states.Then we use current machine learning and deep learning techniques to automatically classify a random state of two,three,and four qubits without the need to compute the amount of the different types of entanglement in each run;rather this is done only in the learning process.The technique shows high,near-perfect,accuracy in the case of pure states.As expected,this accuracy drops,more or less,when dealing with mixed states and when increasing the number of parties involved. 展开更多
关键词 entangleMENT machine learning CLASSIFICATION neural network
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Perfect entanglement swapping of W states
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作者 Sajede Harraz Yueyan Wang Shuang Cong 《Communications in Theoretical Physics》 2025年第10期96-105,共10页
In this paper,we propose a perfect entanglement swapping protocol for generating a shared three-qubit W state between two remote parties in a deterministic manner.Our method offers a reliable alternative to existing p... In this paper,we propose a perfect entanglement swapping protocol for generating a shared three-qubit W state between two remote parties in a deterministic manner.Our method offers a reliable alternative to existing probabilistic protocols for W state entanglement swapping,which is crucial for various quantum information processing tasks.We present a detailed quantum circuit design,implemented using the Qiskit simulator,that outlines the preparation of W states and the execution of joint measurements required for the entanglement swapping process.Furthermore,we analyze the effects of imperfect operations and noisy communication channels on the fidelity of the resulting shared W state.To address these challenges,we introduce a weak measurement-based purification method that enhances fidelity in the presence of amplitude damping.Through mathematical analysis and Qiskit simulations,we demonstrate the effectiveness of our proposed protocol,offering a practical solution for high-fidelity W state generation in real-world quantum communication scenarios. 展开更多
关键词 entanglement swapping DECOHERENCE W states Qiskit
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Enhancing entanglement and steering in a hybrid atom–optomechanical system via Duffing nonlinearity
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作者 Ling-Hui Dong Xiao-Jie Wu +1 位作者 Cheng-Hua Bai Shao-Xiong Wu 《Chinese Physics B》 2025年第2期124-131,共8页
We introduce a novel scheme for achieving quantum entanglement and Einstein–Podolsky–Rosen(EPR) steering between an atomic ensemble and a mechanical oscillator within a hybrid atom–optomechanical system. The system... We introduce a novel scheme for achieving quantum entanglement and Einstein–Podolsky–Rosen(EPR) steering between an atomic ensemble and a mechanical oscillator within a hybrid atom–optomechanical system. The system comprises an optical cavity, a two-level atomic ensemble and a mechanical resonator that possesses Duffing nonlinearity. The interaction between these components is mediated by the cavity mode, which is driven by an external laser. Our findings indicate that optimizing the coupling strengths between photons and phonons, as well as between atoms and the cavity,leads to maximal entanglement and EPR steering. The amplitude of the driving laser plays a pivotal role in enhancing the coupling between photons and phonons, and the system maintains robust entanglement and EPR steering even under high dissipation, thereby mitigating the constraints on initial conditions and parameter precision. Remarkably, the Duffing nonlinearity enhances the system's resistance to thermal noise, ensuring its stability and entanglement protection. Our analysis of EPR steering conditions reveals that the party with lower dissipation exhibits superior stability and a propensity to steer the party with higher dissipation. These discoveries offer novel perspectives for advancing quantum information processing and communication technologies. 展开更多
关键词 quantum entanglement EPR steering optomechanical system Duffing nonlinearity
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A Thought Experiment Suggests a Simple Interpretation of Quantum Entanglement
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作者 Qinghua Cui 《Journal of Modern Physics》 2025年第2期286-293,共8页
Quantum entanglement is a bizarre, counterintuitive phenomenon which shows that entangled subatomic particles remain related even when they are far apart, which was described by Einstein as “spooky action at a dista... Quantum entanglement is a bizarre, counterintuitive phenomenon which shows that entangled subatomic particles remain related even when they are far apart, which was described by Einstein as “spooky action at a distance”. Although this phenomenon could be interpreted by a few theories, for example, the famous Copenhagen interpretation which describes that these states exist simultaneously by a wave function, however, there is still no unquestioned theory and it continues to puzzle people around the world. Here we propose a hypothesis that gravity cuts out stop functioning between subatomic particles based on the observations of a thought experiment. It is well known that the Universe is filled with various subatomic particles (e.g. cosmic neutrino background, CνB) and gravity is a universal force making any particle in the Universe attract any other. Based on these observations, it is expected that the CνB particles walking abreast will be combined together by their gravity after some time/distance, which will thus result in a greatly uneven distribution of CνB. However, the observational evidence showed that CνB is highly isotropic and homogenous, suggesting that gravity would no longer work at the subatomic scale. Thus, the relation of the paired subatomic particles would become some pure correlation of mass (or equivalent energy) status. In this case, time would be not required anymore due to the ineffectiveness of gravity. The proposed new interpretation matches the experimental observations well and finally possible thought experiments are presented to test this theory. 展开更多
关键词 Quantum entanglement GRAVITY Cosmic Neutrino Background Subatomic Particles
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