共查询到16条相似文献,搜索用时 375 毫秒
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基于模式匹配法建立了矩形槽同轴布拉格结构的全波耦合分析模型, 推导出了不同模式反射率和传输率的计算式, 并采用公开报道的实验数据验证了该理论模型. 在此基础上就本文理论与其他相关的理论方法进行了比较, 发现以前的理论近似模型由于忽略了矩形槽中的消失模而使传输率的频率响应曲线发生偏差. 本文建立的理论方法有望为矩形槽同轴布拉格结构的特性研究和工程实践提供一种理论分析手段.
关键词:
同轴布拉格结构
矩形波纹
模式匹配法
模式耦合 相似文献
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利用模式匹配法建立了分析波纹参数具有随机误差的矩形槽同轴布拉格结构反射特性的理论模型,并以一个以基模(TEM)工作于220GHz附近的矩形槽同轴布拉格结构为例,研究了矩形凹槽的深度、宽度、周期长度以及位置的随机误差对其反射率频率响应的影响。数值模拟结果表明:在给定的误差范围条件下,凹槽宽度与位置的随机误差对该结构的反射性能影响较小,而凹槽深度与周期长度的随机误差是影响结构反射特性的主要因素,因此在结构的加工制备过程中应视器件性能要求严格控制两者的制造公差。 相似文献
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计算了同轴波纹慢波结构的色散特性,分析了波纹周期长度、波纹幅值大小以及同轴内导体半径对慢波结构色散特性的影响。研究表明内导体的存在使系统截止频率升高,系统尺寸可比普通波纹波导慢波系统更大, 并且可以采用大半径电子注并工作在低磁场状态。运用Magic软件对同轴波纹返波管进行了数值模拟, 发现同轴波导内场分布有利于注波互作用,在数值模拟基础上设计出高效率、低磁场的非均匀同轴波纹返波管,互作用效率达60%,聚束磁场小于1 T。 相似文献
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采用基于Ansoft HFSS的电磁仿真平台,研究了一个工作于Ka波段(37.5 GHz附近)的缺陷态同轴布拉格波导在不同的开槽方式及缺陷位置条件下的传输特性。结果表明:该波导只有在内外导体壁单面开槽并引入缺陷,或者双面开槽且两个开槽面同时引入缺陷的条件下才能够有效地产生出传输通带;对于后者而言,将内外导体壁的波纹初始相位差设置为且让缺陷位于波导中间时,可以获得带宽极窄、阻带抑制范围较宽的传输通带,此时,给内外导体壁的缺陷引入适度的错位能够对通带的中心频率、带宽等性能指标起到微调作用,而引入大间距的错位则能够在禁带中产生出多个通带,从而起到多通道滤波的作用。 相似文献
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A theoretical analysis is made of the relative intensity noise (RIN) in tunable two- and three-section distributed Bragg reflector (DBR) lasers by taking into account the actual frequency dependence of the Bragg reflector. The RIN is shown to depend significantly on the tuning current, especially at low frequencies and for low and moderate values of the grating coupling coefficient. For high values of this coefficient the dependence is insignificant when the tuning is performed through the DBR section, in accordance with the experimental results recently reported. The RIN spectrum is more significantly affected, however, when the phase control current in the three-section device is used for tuning. 相似文献
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Iatrou C.T. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1996,24(3):596-605
In this paper, the mode-selective properties of coaxial gyrotron resonators are discussed for different cavity configurations. Expressions are derived for the ohmic loading of a coaxial conductor with longitudinal corrugations where the RF field inside the corrugations is fully taken into account, and for the diffractive quality factor in coaxial cavities with tapered inner conductor relative to that of an empty cylindrical cavity. The competing action of a kind of “surface mode” that appears in corrugated structures is investigated by considering its diffractive and ohmic quality factors. Additional mode competition problems that can arise in coaxial cavities with corrugated inner conductor due to second cyclotron harmonic interaction are investigated and solutions to the problem are proposed 相似文献
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Qi-Qi Wang 《中国物理 B》2022,31(9):94204-094204
Broad area semiconductor laser (BAL) has poor lateral beam quality due to lateral mode competition, which limits its application as a high-power optical source. In this work, the distributed Bragg reflector laser diode with tapered grating (TDBR-LD) is studied. By changing the lateral width, the tapered grating increases the loss of high-order lateral modes, thus improving the lateral characteristics of the laser diode. The measuring results show that the TDBR-LD can achieve a single-lobe output under 0.9 A. In contrast to the straight distributed Bragg reflector laser diode (SDBR-LD), the lateral far field divergence of TDBR-LD is measured to be 5.23° at 1 A, representing a 17% decline. The linewidth of TDBR-LD is 0.4 nm at 0.2 A, which is reduced by nearly 43% in comparison with that of SDBR-LD. Meanwhile, both of the devices have a maximum output power value of approximate 470 mW. 相似文献
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Spatial and spectral filtering of tapered lasers by using tapered distributed Bragg reflector grating 下载免费PDF全文
Jing-Jing Yang 《中国物理 B》2022,31(8):84203-084203
A 1040 nm tapered laser with tapered distributed Bragg reflector (DBR) grating is designed and fabricated. By designing the grating with tapered layout, the tapered DBR grating exhibits the scattering effect on side backward-traveling waves, thus achieving additional suppression of parasitic oscillation. Under the suppression of parasitic oscillation, the spatial and spectral characteristics of the tapered laser are improved. The experimental results show that a near-Gaussian far-field distribution and a kink-free P-I characteristics are achieved, and a single peak emission with a wavelength of 1046.84 nm and a linewidth of 56 pm is obtained. 相似文献