Theoretical and numerical analysis of very high harmonic superconducting tunnel junction mixers
Theoretical and numerical analysis of very high harmonic superconducting tunnel junction mixers
复制标题
甚高谐波超导隧道结混频器的理论与数值分析
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
G. Yassin
中科院分区：
文献类型：
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作者：
P. Kittara;S. Withington;G. Yassin
我们描述了一个非常高次谐波超导体-绝缘体-超导体（SIS）混频器的非线性，量子力学行为的建模过程。典型的混频器由10- 15 GHz的强微波源泵浦，这导致高谐波（20-40）电流流动，其中任何一个都可以用作本机振荡器，将亚毫米波信号下变频到1- 8 GHz的低微波频率。这种操作模式对于测量传统SIS混频器的波束图案是有吸引力的，因为仅需要单个亚毫米波源。我们使用13.5GHz微波源的20次谐波进行了模拟，将271.4GHz信号下变频到1.4GHz中频。这些模拟清楚地表明，即使在相对较高的射频信号功率水平下，也可以实现线性下变频;尽管在选择工作点时需要小心。在模拟中看到的行为模式与最近发表的实验结果非常一致。
We describe a procedure for modeling the nonlinear, quantum-mechanical behavior of very high harmonic superconductor-insulator-superconductor (SIS) mixers. A typical mixer is pumped by a strong microwave source at 10–15GHz, which causes high-harmonic (20–40) currents to flow, any one of which can be used as a local oscillator to downconvert a submillimeter-wave signal to a low microwave frequency, 1–8GHz. This mode of operation is attractive for measuring the beam patterns of conventional SIS mixers, because only a single submillimeter-wave source is needed. We conducted simulations using the 20th harmonic of a 13.5GHz microwave source, downconverting a 271.4GHz signal to a 1.4GHz intermediate frequency. These simulations clearly show that linear downconversion can be achieved even for relatively high levels of rf signal power; although, care is needed when choosing the operating point. The patterns of behavior seen in the simulations are in remarkable agreement with recently published experimental results.