Wheeler's delayed-choice experiment demonstrates wave-particle duality of particles using different experimental configurations of a Mach-Zehnder interferometer. In a quantum version of this experiment, the wave-p...
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Wheeler's delayed-choice experiment demonstrates wave-particle duality of particles using different experimental configurations of a Mach-Zehnder interferometer. In a quantum version of this experiment, the wave-particle behaviour of photons can be observed by controlling presence or absence of the second beam splitter. Here, we implement a delayed-choice experiment with dual selections based on entangled photons, experimentally controlling both of two beam splitters in the Mach-Zehnder interferometer, where the presence and absence of the second beam splitter are simultaneously controlled through path encoding. Our experiment reveals the wave-particle behavior of single photons under different configurations of two beam splitters. We further discuss the scenario when two beam splitters are in a quantum superposition of being present and absent, photons will be in a wave-particle quantum superposition state.
Metamaterials can control and manipulate acoustic/elastic waves on a subwavelength scale using cavities or additional ***,the large cavity and weak stiffness components of traditional metamaterials may cause a conflic...
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Metamaterials can control and manipulate acoustic/elastic waves on a subwavelength scale using cavities or additional ***,the large cavity and weak stiffness components of traditional metamaterials may cause a conflict between vibroacoustic reduction and load-bearing capacity,and thus limit their ***,we propose a lightweight multifunctional metamaterial that can simultaneously achieve low-frequency sound insulation,broadband vibration reduction,and excellent load-bearing performance,named as vibroacoustic isolation and bearing metamaterial(VIBM).The advent of additive manufacturing technology provides a convenient and reliable method for the fabrication of VIBM *** results show that the compressive strength of the VIBM is as high as 9.71 MPa,which is nearly 87.81%higher than that of the conventional grid structure(CGS)under the same volume ***,the vibration and sound transmission are significantly reduced over a low and wide frequency range,which agrees well with the experimental data,and the reduction degree is obviously larger than that obtained by the *** design strategy can effectively realize the key components of metamaterials and improve their application scenarios.
Boron arsenide(BAs) is a promising integrated circuit thermal management material with ultra-high thermal conductivity(κ) and exceptional semiconductor properties. In practical devices, mechanical stress and strain c...
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Boron arsenide(BAs) is a promising integrated circuit thermal management material with ultra-high thermal conductivity(κ) and exceptional semiconductor properties. In practical devices, mechanical stress and strain caused by thermal expansion inevitably affect the thermodynamic properties of heat sink materials. Consequently, investigation of the effects of stress and strain on the κ of BAs is essential. Accurate assessment and regulation of the κ and phonon heat transport of BAs requires consideration of both three-phonon(3ph) and four-phonon(4ph) interactions. However, anharmonicity computation using density functional theory is computationally expensive, particularly for the fourth-order interatomic force constants. This work uses a machine learning-driven moment tensor potential method to evaluate higher-order anharmonicity and extends it to include fourth-order forces, accelerating the calculations significantly. Results show that the κ of BAs calculated using the moment tensor potential method when considering both 3ph and 4ph processes agrees well with experimental data. In contrast,considering the 3ph interaction alone causes κ to be overestimated. The machine learning approach reduces computational costs by approximately 94% while maintaining comparable accuracy to density functional theory. By solving the phonon Boltzmann transport equation, the thermal transport properties of BAs under biaxial tensile strains ranging up to 7% are evaluated. BAs shows an anomalous κ enhancement when including both 3ph and 4ph interactions, with a maximum enhancement of 15% at a small strain of 1%, primarily because of the weakening of the 3ph scattering. Beyond 2% strain, both the 3ph and 4ph scattering rates increase significantly, causing shorter phonon lifetimes and a monotonic reduction in κ. Additionally, the κ temperature dependence under strain is explored, highlighting temperature's role in modulating phonon scattering. This study provides machine learning-driven i
Considerable progress has been made in synthesizing two-dimensional(2D)materials by exfoliating layered ***;for tremendous non-layered inorganic materials;especially magnet solids;usually with closely packed bulk phas...
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Considerable progress has been made in synthesizing two-dimensional(2D)materials by exfoliating layered ***;for tremendous non-layered inorganic materials;especially magnet solids;usually with closely packed bulk phases by strong chemical bonds;it is challenging to obtain their high-quality 2D ***;we highlighted a new structure of free-standing ferromagnetic nanosheets featuring(111)*** magnet;Fe_(3)O_(4);its inversed spinel crystalline has limited abilities to exfoliate into 2D forms and rarely exists as free-standing nanosheets owing to aggregation induced by magnetic *** realized a breakthrough in achieving free-standing ferromagnetic nanosheets with dramatically surpassing size limitations via topotactic conversion from layered *** Fe_(3)O_(4) nanosheets exhibited a maximum width of 60μm while onl y~4 nm thick;prominently exposing(111)facets.2D Fe_(3)O_(4) behaved anisotropic magnetism;which displayed a 4.6 emu g^(-1) moment(H=500 Oe)in the(111)plane but 2.1 emu g^(-1)out of the(111)plane;indicating a(111)in-plane easy *** anticipated our topotactic conversion strategy would inspire the creation of 2D non-layered materials and enrich the 2D materials family.
With the development of deep learning in recent years, code representation learning techniques have become the foundation of many software engineering tasks such as program classification [1] and defect detection. Ear...
With the development of deep learning in recent years, code representation learning techniques have become the foundation of many software engineering tasks such as program classification [1] and defect detection. Earlier approaches treat the code as token sequences and use CNN, RNN, and the Transformer models to learn code representations.
As a typical tungsten-based composite consisting of tungsten(W)particles and matrix phase,tungsten heavy alloys(WHAs)are extensively utilized in the military due to their exceptional strength and high ***,the large gr...
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As a typical tungsten-based composite consisting of tungsten(W)particles and matrix phase,tungsten heavy alloys(WHAs)are extensively utilized in the military due to their exceptional strength and high ***,the large grain size(＞30 μm)of powder metallurgy liquid phase sintered(LPS)WHAs and the low strength of the matrix phase limit the further improvement of the *** this work,high-density ultrafine WHAs were fabricated by two-step low-temperature sintering,and the density of the alloy reached 17 g/cm3 with an average W particle size of 7.81 μ***,the eutectic reaction be-tween Ni and Ta was controlled to generate dispersed nano-Ni3Ta phases in situ in the matrix phase,fur-ther improving the strength of the *** the synergistic strengthening effect of fine-grain strength-ening,dispersion strengthening,and solid solution strengthening,the average ultimate tensile strength of the alloy reached 1190.39 *** the same time,the alloy maintained good elongation with a total elon-gation of 20.8％due to the good co-grid interface orientation between the Ni3Ta phase and the matrix *** study provides a new idea for developing high-strength WHAs and has a guiding significance for developing Ni-based alloys.
The T1(Al2CuLi)phase is one of the most effective strengthening nanoscale-precipitate in Al-Cu alloys with ***,its formation and evolution still need to be further clarified during aging due to the complex precipitati...
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The T1(Al2CuLi)phase is one of the most effective strengthening nanoscale-precipitate in Al-Cu alloys with ***,its formation and evolution still need to be further clarified during aging due to the complex precipitation ***,a detailed investigation has been carried out on the atomic struc-tural evolution of T1 precipitate in an aged Al-Cu-Li-Mg-Ag alloy using state-of-the-art Cs-corrected high-angle annular dark field(HAADF)-coupled with integrated differential phase contrast(iDPC)-scanning transmission electron microscopy(STEM)and energy-dispersive X-ray spectroscopy(EDXS)*** intermediate T1'phase between T1p and T1 phase,with a crystal structure and orientation rela-tionship consistent with T1,but exhibiting different atomic occupancy and chemical composition was *** observed the atomic structural transformation from T1p to T1'phase(fcc→hcp),involving only 1/12<112>Al shear *** calculation results validated our proposed structural models and the precipitation ***,the distributions of minor solute elements(Ag,Mg,and Zn)in the pre-cipitates exhibited significant *** findings may contribute to a further understanding of the nucleation mechanism of T1 precipitate.
With the rapid development of modern communication technology, spectrum resources have become non-renewable and precious resources, and the terahertz frequency band has entered people's vision. Nowadays, terahertz...
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With the rapid development of modern communication technology, spectrum resources have become non-renewable and precious resources, and the terahertz frequency band has entered people's vision. Nowadays, terahertz communication technology has become one of the core technologies for future high-capacity and high-rate communication. This paper discusses and analyzes the core technologies related to the field of terahertz *** introduce the characteristics, domestic and international comparisons and development trends of the core devices for terahertz communication, and also introduce and discuss the terahertz solid-state frequency mixing communication system, terahertz direct modulation communication system, and terahertz optoelectronic communication ***, we summarize the development of terahertz communication technology and the outlook of future applications.
Cryogenic ion traps offer substantial advantages over their room-temperature counterparts,particularly in terms of stable ion confinement and ***,this technological advancement has introduced a significant challenge,n...
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Cryogenic ion traps offer substantial advantages over their room-temperature counterparts,particularly in terms of stable ion confinement and ***,this technological advancement has introduced a significant challenge,namely the generation of additional vibrational *** noise is pronounced during the compression and expansion phases of the Gifford–McMahon cycle refrigerator and stems from the mechanical operation of the cold *** residual vibrational noise can modulate the Rabi oscillation frequency,thereby compromising the fidelity of the quantum logic *** this study,we quantitatively assess the impact of residual vibrational noise and introduce an innovative strategy for its *** strategy was designed to reduce superimposed potential fluctuations within a cryogenic surface electrode ion *** measured residual vibrational noise was used for real-time feedback *** the inverse determination of the compensating potential for a stable superimposed trapping potential is an inherently ill-posed problem considering known measurement noise *** applying quadratic programming,we numerically calculated the optimal time series for the compensation *** ensemble of these compensation voltages was applied in real time to the static compensation *** this method is in the theoretical stage,we believe that it can effectively suppress the translation induced by vibrational noise and foster the creation of a stable superimposed harmonic *** deployment of this technique is expected to substantially improve the accuracy of quantum operations,thereby fueling the evolution of quantum technologies.
Capacitor-based pulsed power supply (PPS) is widely used in fields related to electromagnetic launch, plasma, and materials' synthesis, modification and processing. As industrial applications place higher requirem...
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