- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Resonant Enhancement of THz Radiation Through Vertically Aligned Carbon Nanotubes Array by Applying Wiggler Magnetic Field
摘要： The present analysis develops a novel theory of terahertz radiation generation by beating of two laser beams, incident obliquely on the array of vertically aligned carbon nanotubes (CNTs) in the presence of an external wiggler magnetic field. The array of CNTs behaves as nanoantenna to generate THz radiations. The incident lasers exert a ponderomotive force on the electrons of the CNTs to produce nonlinear oscillatory velocity, which beats with the applied wiggler magnetic field. This beating produces a nonlinear current at (ω2 ? ω1, k2 ? k1 + k0) which acts as an antenna to produce the THz radiation. We observe that when the beat frequency (ω2 ? ω1) lies near the effective plasmon frequency of the CNTs, strong THz radiation is produced due to a resonant interaction of the laser with CNT electrons. The externally applied wiggler magnetic field enhances the efficiency of THz radiation of nanoantenna by providing the necessary momentum to the generated THz radiation. We explore the impact of radius and length of nanotubes on the efficiency of THz generation. The generated THz power is enhanced at an optimum angle of incidence of lasers with an array of CNTs.
关键词： THz radiation,Carbon nanotubes,Antenna theory,Wiggler magnetic field,Plasma,Nanotechnology
更新于2025-09-23 15:23:52
-
Electromagnetic Wave Theory for Calculation of Exact Magnetic Field in Case of BWO
摘要： Overall efficiency of high power microwave generating device depends upon input current in the form of electron beam and currents required for electromagnets. In order to increase the efficiency of device, if electromagnets are replaced by permanent magnets, overall efficiency of device shall increase. So, calculation of exact magnetic field is required. In this paper, the exact relation of magnetic field required in high power microwave generation using Backward Wave Oscillator (BWO) is found. BWO interacts with slow waves and is the most promising device to produce high power microwaves. The interaction involves the beams from high current density and the waveguide mode. An exact relation that specifically relates the various parameters of the waveguide like slow wave structures (SWS) dimensions, input beam voltage and operational frequency with axial magnetic field is derived. The derived equation gives calculation of exact values of magnetic field for focusing of beams. Theoretical and simulated work show good agreement with the previously available experimental data. So, with the derived electromagnetic wave relation exact value of magnetic field is calculated for desired frequency and power regime.
关键词： High current electron,High power microwave,Wiggler,Magnetic field,Oscillator
更新于2025-09-04 15:30:14