Space applications impose strict requirements on gyroscope design including high accuracy, precision, shock resistance, reduced non-linearity and sensitivity to external factors such as temperature variation. Vibratin...
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A measurement of the Higgs boson (H) production via vector boson fusion (VBF) and its decay into a bottom quark-antiquark pair (bb¯) is presented using proton-proton collision data recorded by the CMS experiment ...
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The complex dielectric constants of GaAs1−xBix alloys grown by molecular beam epitaxy with x=0% to 17% have been measured over the spectral range from 0.37 to 9.1 eV using spectroscopic ellipsometry. Critical points i...
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The complex dielectric constants of GaAs1−xBix alloys grown by molecular beam epitaxy with x=0% to 17% have been measured over the spectral range from 0.37 to 9.1 eV using spectroscopic ellipsometry. Critical points in the joint density of states have been analyzed by fitting the line shape of the Van Hove singularities in the dielectric function derived from the ellipsometry data. The critical points generally match similar critical points in the dielectric function of GaAs with at least one alternative critical point. The energy of the critical points involving transitions from the top of the valence band show a strong dependence on Bi concentration similar to the composition dependence of the band gap, while the other critical points have a weaker dependence on Bi concentration. The measured composition dependence of the band gap and the energy of the split-off hole band are in good agreement with density functional calculations. The composition dependence of the index of refraction in the vicinity of the band gap for GaAs1−xBix alloys is an order of magnitude larger than the composition dependence of the index of refraction in Ga1−xInxAs alloys.
One of the most accurate approaches for calculating lattice thermal conductivity,κ_(l),is solving the Boltzmann transport equation starting from third-order anharmonic force *** addition to the underlying approximati...
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One of the most accurate approaches for calculating lattice thermal conductivity,κ_(l),is solving the Boltzmann transport equation starting from third-order anharmonic force *** addition to the underlying approximations of ab-initio parameterization,two main challenges are associated with this path:high computational costs and lack of automation in the frameworks using this methodology,which affect the discovery rate of novel materials with ad-hoc ***,the Automatic Anharmonic Phonon Library(AAPL)is *** efficiently computes interatomic force constants by making effective use of crystal symmetry analysis,it solves the Boltzmann transport equation to obtain κ_(l),and allows a fully integrated operation with minimum user intervention,a rational addition to the current high-throughput accelerated materials development framework ***“experiment ***”study of the approach is shown,comparing accuracy and speed with respect to other available packages,and for materials characterized by strong electron localization and *** AAPL with the pseudo-hybrid functional ACBN0 is possible to improve accuracy without increasing computational requirements.
Mixed-numerology transmission is proposed to support a variety of communication scenarios with diverse requirements. However, as the orthogonal frequency division multiplexing (OFDM) remains as the basic waveform, the...
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The ability to monitor and control distinct states is at the heart of emerging quantum technologies. The valley pseudospin in transition metal dichalcogenide (TMDC) monolayers is a promising degree of freedom for such...
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The ability to monitor and control distinct states is at the heart of emerging quantum technologies. The valley pseudospin in transition metal dichalcogenide (TMDC) monolayers is a promising degree of freedom for such control, with the optical Stark effect allowing for valley-selective manipulation of energy levels in WS2 and WSe2 using ultrafast optical pulses. Despite these advances, understanding of valley-sensitive optical Stark shifts in TMDCs has been limited by reflectance-based detection methods where the signal is small and prone to background effects. More sensitive polarization-based spectroscopy is required to better probe ultrafast Stark shifts for all-optical manipulation of valley energy levels. Here, we show time-resolved Kerr rotation to be a more sensitive probe of the valley-selective optical Stark effect in monolayer TMDCs. Compared to the established time-resolved reflectance methods, Kerr rotation is less sensitive to background effects. Kerr rotation provides a fivefold improvement in the signal-to-noise ratio of the Stark effect optical signal and a more precise estimate of the energy shift. This increased sensitivity allows for observation of an optical Stark shift in monolayer MoS2 that exhibits both valley and energy selectivity, demonstrating the promise of this method for investigating this effect in other layered materials and heterostructures.
In hyperbolic two-dimensional (2D) materials, energy is channeled into their deep subwavelength polaritonic modes via four narrow beams. Here, we consider the launching of surface polaritons in hyperbolic 2D materials...
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In hyperbolic two-dimensional (2D) materials, energy is channeled into their deep subwavelength polaritonic modes via four narrow beams. Here, we consider the launching of surface polaritons in hyperbolic 2D materials and demonstrate that efficient unidirectional excitation is possible with an elliptically polarized electric dipole, with the optimal choice of dipole ellipticity depending on the materials' optical constants. The selection rules afforded by the choice of dipole polarization allow turning off up to two beams, and even three if the dipole is placed close to an edge. This makes the dipole a directionally switchable beacon for the launching of subdiffractional polaritonic beams, a potential logical gate. We develop an analytical approximation of the excitation process which describes well the results of the numerical simulations and affords a simple physical interpretation.
Quantum computing has seen tremendous progress in past years. Due to implementation complexity and cost, the future path of quantum computation is strongly believed to delegate computational tasks to powerful quantum ...
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Quantum computing has seen tremendous progress in past years. Due to implementation complexity and cost, the future path of quantum computation is strongly believed to delegate computational tasks to powerful quantum servers on the cloud. Universal blind quantum computing (UBQC) provides the protocol for the secure delegation of arbitrary quantum computations, and it has received significant attention. However, a great challenge in UBQC is how to transmit a quantum state over a long distance securely and reliably. Here, we solve this challenge by proposing a resource-efficient remote blind qubit preparation (RBQP) protocol, with weak coherent pulses for the client to produce, using a compact and low-cost laser. We experimentally verify a key step of RBQP—quantum nondemolition measurement—in the field test over 100 km of fiber. Our experiment uses a quantum teleportation setup in the telecom wavelength and generates 1000 secure qubits with an average fidelity of (86.9±1.5)%, which exceeds the quantum no-cloning fidelity of equatorial qubit states. The results prove the feasibility of UBQC over long distances, and thus serves as a key milestone towards secure cloud quantum computing.
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