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A three-dimensional quantum-mechanical method is used for modeling quantum tunneling and photon-assisted field emission processes in vertical and lateral vacuum nanotriodes. The electron transport through the devices is computed using a transfer-matrix technique. The possibility of using vacuum nanotriodes in current rectification is investigated at low voltages in a quasi-static and a high-frequency analyses. The obtained results show that a great enhancement in the rectification properties is achievable when a DC bias is applied between the gate and the collector. By comparing the results of the vertical and the lateral-type devices, it is shown that the former is superior in current rectification, while the latter provides higher values of current density. Furthermore, the high-frequency analysis shows that incident radiation results in photon-assisted current emission. It also demonstrates that the vacuum nanotriode can be much more efficient than the vacuum nanodiode in rectifying high-frequency signals. Published [ABSTRACT FROM AUTHOR]

Generalized Snoek's law proposed in an integral form by Acher and coauthors is a useful tool for investigation of high-frequency properties of magnetic materials. This integral law referred to as Acher's law allows for evaluating the ultimate performance of RF and microwave devices which employ magnetic materials. It may also be helpful in obtaining useful information on the structure and morphology of the materials. The key factor in practical application of Acher's law is an opportunity to employ either measured or calculated data available over a finite frequency range. The paper uses simple calculations to check the applicability of Acher's law in cases when the frequency range is limited and the magnetic loss peak is comparatively wide and has a distorted shape. The cases of large magnetic damping, pronounced skin effect, and inhomogeneity of the material are considered. It is shown that in most cases calculation of the integral through fitting of actual magnetic frequency dispersion by the Lorentzian dispersion law results in accurate estimations of the ultimate high-frequency performance of magnetic materials. [ABSTRACT FROM AUTHOR]

Recently, interest has been shown in research on the module-integrated converter (MIC) in smallscale photovoltaic (PV) generation. In an MIC, the voltage boosting high frequency transformer should be designed to be compact in size and have high efficiency. In response to the need to satisfy these requirements, this paper presents a coupled electromagnetic analysis model of a transformer connected with a high frequency switching DC-DC converter circuit while considering thermal characteristics due to the copper and core losses. A design optimization procedure for high efficiency is also presented using this design analysis method, and it is verified by the experimental result. [ABSTRACT FROM AUTHOR]