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• we take advantage of the advantages of magnetron sputtering and pulsed laser sputtering to build a magnetron pulsed laser co-sputtering system. • By studying the VSN structure, we propose a new inverted pyramid VSN structure. • The reverse-pyramidal VSN exhibits the highest dielectric constant (428.08) and dielectric loss (0.0212) while maintaining a high tunability (78.69 %). • The inverted pyramid VSN structure improves device tuning performance and increases device lifetime. Microwaves are often used in communication engineering, including in microwave relays as well as multichannel, mobile, and satellite communications. To meet the demand for a "small, light, thin, and precise" modern electronic machine, developing highly tunable microwave materials to manufacture miniaturized microwave devices has become a top priority. Ferroelectric materials are excellent microwave materials, showing outstanding dielectric properties and tunability. Introducing low dielectric loss oxides in the construction of vertical self-assembly nanocomposites (VSNs) effectively improves their tunability and reduces dielectric loss. However, the optimal doping content of simple VSN films limits further improvement of tunability. Herein, we propose a strategy-gradient VSN to achieve combined improvement in tunability and dielectric constant by designing a sputtering and pulsed laser co-deposition. The resulting VSN composite film has a dielectric constant of 428.08, a dielectric loss of 0.0212, and a tunability of 78.69 %. Our results contribute to the development of filters and have broad application prospects in the microwave industry. we propose a strategy-gradient vertical self-assembly structure (figure c) to achieve a joint improvement in the tunability and dielectric constant (figure d) by designing a sputtering and pulsed laser codeposition (figure a). [Display omitted] [ABSTRACT FROM AUTHOR]

The production of Bcand B*cmesons at a Z-factory (an e+e-collider operating at energies around the Zpole) is calculated up to the next-to-leading order (NLO) QCD accuracy. The results show that the dependence of the total cross sections on the renormalization scale μ is suppressed by the corrections, and the NLO corrections enhance the total cross sections of Bcby 52% and of B*cby 33% when the renormalization scale is taken at μ= 2mb. To observe the various behaviors of the production of the mesons Bcand B*c, such as the differential cross section vs. the out-going angle, the forward-backward asymmetry, and the distribution vs. the energy fraction zup to NLO QCD accuracy as well as the relevant K-factor (NLO to LO) for the production, are calculated, and it is pointed out that some of the observables obtained in the present work may be used as a specific precision test of the standard model.

Abstract: We analyze the cross section of e + e − → τ +µ− within the frameworks of SM and its Z′ extension. The theoretical prediction of the SM on the total cross section is suppressed by the tiny neutrino masses. On the other hand, the contributions from Z′ to the cross section are enhanced drastically because of the tree level FCNC couplings among Z′ and leptons.